@article {49817, title = {Therapeutic relevance of the protein phosphatase 2A in cancer}, journal = {Oncotarget.com}, year = {2016}, month = {Jul-09-2017}, doi = {10.18632/oncotarget.11399}, url = {https://www.oncotarget.com/article/11399}, author = {Cunningham, Chelsea E. and Li, Shuangshuang and Vizeacoumar, Frederick S. and Bhanumathy, Kalpana Kalyanasundaram and Lee, Joo Sang and Parameswaran, Sreejit and Furber, Levi and Abuhussein, Omar and Paul, James M. and McDonald, Megan and Templeton, Shaina D. and Shukla, Hersh and El Zawily, Amr M. and Boyd, Frederick and Alli, Nezeka and Mousseau, Darrell D. and Geyer, Ron and Bonham, Keith and Anderson, Deborah H. and Yan, Jiong and Yu-Lee, Li-Yuan and Weaver, Beth A. and Uppalapati, Maruti and Ruppin, Eytan and Sablina, Anna and Freywald, Andrew and Vizeacoumar, Franco J.} } @article {49794, title = {Transcriptome Remodeling in Trypanosoma cruzi and Human Cells during Intracellular Infection.}, journal = {PLoS Pathog}, volume = {12}, year = {2016}, month = {2016 Apr}, pages = {e1005511}, abstract = {

Intracellular colonization and persistent infection by the kinetoplastid protozoan parasite, Trypanosoma cruzi, underlie the pathogenesis of human Chagas disease. To obtain global insights into the T. cruzi infective process, transcriptome dynamics were simultaneously captured in the parasite and host cells in an infection time course of human fibroblasts. Extensive remodeling of the T. cruzi transcriptome was observed during the early establishment of intracellular infection, coincident with a major developmental transition in the parasite. Contrasting this early response, few additional changes in steady state mRNA levels were detected once mature T. cruzi amastigotes were formed. Our findings suggest that transcriptome remodeling is required to establish a modified template to guide developmental transitions in the parasite, whereas homeostatic functions are regulated independently of transcriptomic changes, similar to that reported in related trypanosomatids. Despite complex mechanisms for regulation of phenotypic expression in T. cruzi, transcriptomic signatures derived from distinct developmental stages mirror known or projected characteristics of T. cruzi biology. Focusing on energy metabolism, we were able to validate predictions forecast in the mRNA expression profiles. We demonstrate measurable differences in the bioenergetic properties of the different mammalian-infective stages of T. cruzi and present additional findings that underscore the importance of mitochondrial electron transport in T. cruzi amastigote growth and survival. Consequences of T. cruzi colonization for the host include dynamic expression of immune response genes and cell cycle regulators with upregulation of host cholesterol and lipid synthesis pathways, which may serve to fuel intracellular T. cruzi growth. Thus, in addition to the biological inferences gained from gene ontology and functional enrichment analysis of differentially expressed genes in parasite and host, our comprehensive, high resolution transcriptomic dataset provides a substantially more detailed interpretation of T. cruzi infection biology and offers a basis for future drug and vaccine discovery efforts.

}, issn = {1553-7374}, doi = {10.1371/journal.ppat.1005511}, author = {Li, Yuan and Shah-Simpson, Sheena and Okrah, Kwame and Belew, A Trey and Choi, Jungmin and Caradonna, Kacey L and Padmanabhan, Prasad and Ndegwa, David M and Temanni, M Ramzi and Corrada Bravo, Hector and El-Sayed, Najib M and Burleigh, Barbara A} } @article {49616, title = {The Theory and Practice of Genome Sequence Assembly}, journal = {Annu Rev Genomics Hum GenetAnnu Rev Genomics Hum Genet}, volume = {16}, year = {2015}, note = {Simpson, Jared T
Pop, Mihai
eng
2015/05/06 06:00
Annu Rev Genomics Hum Genet. 2015 Aug 24;16:153-72. doi: 10.1146/annurev-genom-090314-050032. Epub 2015 Apr 22.}, month = {Aug 24}, pages = {153-72}, abstract = {The current genomic revolution was made possible by joint advances in genome sequencing technologies and computational approaches for analyzing sequence data. The close interaction between biologists and computational scientists is perhaps most apparent in the development of approaches for sequencing entire genomes, a feat that would not be possible without sophisticated computational tools called genome assemblers (short for genome sequence assemblers). Here, we survey the key developments in algorithms for assembling genome sequences since the development of the first DNA sequencing methods more than 35 years ago.}, keywords = {algorithm, Bioinformatics, genome sequencing, sequence assembly, shotgun sequencing}, isbn = {1545-293X (Electronic)
1527-8204 (Linking)}, author = {Simpson, J. T. and Pop, M.} } @article {49539, title = {Transcriptomic profiling of gene expression and RNA processing during Leishmania major differentiation.}, volume = {43}, year = {2015}, month = {2015 Aug 18}, pages = {6799-813}, abstract = {

Protozoan parasites of the genus Leishmania are the etiological agents of leishmaniasis, a group of diseases with a worldwide incidence of 0.9-1.6 million cases per year. We used RNA-seq to conduct a high-resolution transcriptomic analysis of the global changes in gene expression and RNA processing events that occur as L. major transforms from non-infective procyclic promastigotes to infective metacyclic promastigotes. Careful statistical analysis across multiple biological replicates and the removal of batch effects provided a high quality framework for comprehensively analyzing differential gene expression and transcriptome remodeling in this pathogen as it acquires its infectivity. We also identified precise 5{\textquoteright} and 3{\textquoteright} UTR boundaries for a majority of Leishmania genes and detected widespread alternative trans-splicing and polyadenylation. An investigation of possible correlations between stage-specific preferential trans-splicing or polyadenylation sites and differentially expressed genes revealed a lack of systematic association, establishing that differences in expression levels cannot be attributed to stage-regulated alternative RNA processing. Our findings build on and improve existing expression datasets and provide a substantially more detailed view of L. major biology that will inform the field and potentially provide a stronger basis for drug discovery and vaccine development efforts.

}, issn = {1362-4962}, doi = {10.1093/nar/gkv656}, author = {Dillon, Laura A L and Okrah, Kwame and Hughitt, V Keith and Suresh, Rahul and Li, Yuan and Fernandes, Maria Cecilia and Belew, A Trey and Corrada Bravo, Hector and Mosser, David M and El-Sayed, Najib M} } @article {49614, title = {TIPP:Taxonomic Identification and Phylogenetic Profiling}, journal = {BioinformaticsBioinformatics}, year = {2014}, month = {October 29, 2014}, abstract = {Motivation: Abundance profiling (also called {\textquotedblleft}phylogenetic profiling{\textquotedblright}) is a crucial step in understanding the diversity of a metagenomic sample, and one of the basic techniques used for this is taxonomic identification of the metagenomic reads.Results: We present TIPP (taxon identification and phylogenetic profiling), a new marker-based taxon identification and abundance profiling method. TIPP combines SEPP, a phylogenetic placement method, with statistical techniques to control the classification precision and recall, and results in improved abundance profiles. TIPP is highly accurate even in the presence of high indel errors and novel genomes, and matches or improves on previous approaches, including NBC, mOTU, PhymmBL, MetaPhyler, and MetaPhlAn.Availability: Software and supplementary materials are available at http://www.cs.utexas.edu/users/phylo/software/sepp/tipp-submission/.Contact: warnow@illinois.edu}, author = {Nguyen, Nam-phuong and Mirarab, Siavash and Liu, Bo and Pop, Mihai and Warnow, Tandy} } @article {38580, title = {Three independent determinants of protein evolutionary rate}, journal = {J Mol EvolJ Mol EvolJ Mol Evol}, volume = {76}, number = {3}, year = {2013}, note = {Choi, Sun Shim
Hannenhalli, Sridhar
eng
R01GM085226/GM/NIGMS NIH HHS/
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov{\textquoteright}t
Review
Germany
2013/02/13 06:00
J Mol Evol. 2013 Mar;76(3):98-111. doi: 10.1007/s00239-013-9543-6. Epub 2013 Feb 12.}, month = {Mar}, pages = {98-111}, abstract = {One of the most widely accepted ideas related to the evolutionary rates of proteins is that functionally important residues or regions evolve slower than other regions, a reasonable outcome of which should be a slower evolutionary rate of the proteins with a higher density of functionally important sites. Oddly, the role of functional importance, mainly measured by essentiality, in determining evolutionary rate has been challenged in recent studies. Several variables other than protein essentiality, such as expression level, gene compactness, protein-protein interactions, etc., have been suggested to affect protein evolutionary rate. In the present review, we try to refine the concept of functional importance of a gene, and consider three factors-functional importance, expression level, and gene compactness, as independent determinants of evolutionary rate of a protein, based not only on their known correlation with evolutionary rate but also on a reasonable mechanistic model. We suggest a framework based on these mechanistic models to correctly interpret the correlations between evolutionary rates and the various variables as well as the interrelationships among the variables.}, keywords = {*Evolution, Molecular, *Mutation Rate, Animals, Genes/physiology, Genetic Fitness, HUMANS, Models, Genetic, Protein Biosynthesis/genetics, Protein Folding, Protein Interaction Domains and Motifs/genetics, Proteins/chemistry/*genetics/metabolism}, isbn = {1432-1432 (Electronic)
0022-2844 (Linking)}, author = {Choi, S. S. and Sridhar Hannenhalli} } @article {49764, title = {TIGRFAMs and Genome Properties in 2013.}, journal = {Nucleic Acids Res}, volume = {41}, year = {2013}, month = {2013 Jan}, pages = {D387-95}, abstract = {

TIGRFAMs, available online at http://www.jcvi.org/tigrfams is a database of protein family definitions. Each entry features a seed alignment of trusted representative sequences, a hidden Markov model (HMM) built from that alignment, cutoff scores that let automated annotation pipelines decide which proteins are members, and annotations for transfer onto member proteins. Most TIGRFAMs models are designated equivalog, meaning they assign a specific name to proteins conserved in function from a common ancestral sequence. Models describing more functionally heterogeneous families are designated subfamily or domain, and assign less specific but more widely applicable annotations. The Genome Properties database, available at http://www.jcvi.org/genome-properties, specifies how computed evidence, including TIGRFAMs HMM results, should be used to judge whether an enzymatic pathway, a protein complex or another type of molecular subsystem is encoded in a genome. TIGRFAMs and Genome Properties content are developed in concert because subsystems reconstruction for large numbers of genomes guides selection of seed alignment sequences and cutoff values during protein family construction. Both databases specialize heavily in bacterial and archaeal subsystems. At present, 4284 models appear in TIGRFAMs, while 628 systems are described by Genome Properties. Content derives both from subsystem discovery work and from biocuration of the scientific literature.

}, keywords = {Databases, Protein, Genome, Archaeal, Genome, Bacterial, Genomics, Internet, Markov chains, Molecular Sequence Annotation, Proteins, sequence alignment}, issn = {1362-4962}, doi = {10.1093/nar/gks1234}, author = {Haft, Daniel H and Selengut, Jeremy D and Richter, Roland A and Harkins, Derek and Basu, Malay K and Beck, Erin} } @article {38529, title = {TIGRFAMs and Genome Properties in 2013}, journal = {Nucleic acids researchNucleic Acids Research}, volume = {41}, year = {2013}, note = {http://www.ncbi.nlm.nih.gov/pubmed/23197656?dopt=Abstract}, type = {10.1093/nar/gks1234}, abstract = {TIGRFAMs, available online at http://www.jcvi.org/tigrfams is a database of protein family definitions. Each entry features a seed alignment of trusted representative sequences, a hidden Markov model (HMM) built from that alignment, cutoff scores that let automated annotation pipelines decide which proteins are members, and annotations for transfer onto member proteins. Most TIGRFAMs models are designated equivalog, meaning they assign a specific name to proteins conserved in function from a common ancestral sequence. Models describing more functionally heterogeneous families are designated subfamily or domain, and assign less specific but more widely applicable annotations. The Genome Properties database, available at http://www.jcvi.org/genome-properties, specifies how computed evidence, including TIGRFAMs HMM results, should be used to judge whether an enzymatic pathway, a protein complex or another type of molecular subsystem is encoded in a genome. TIGRFAMs and Genome Properties content are developed in concert because subsystems reconstruction for large numbers of genomes guides selection of seed alignment sequences and cutoff values during protein family construction. Both databases specialize heavily in bacterial and archaeal subsystems. At present, 4284 models appear in TIGRFAMs, while 628 systems are described by Genome Properties. Content derives both from subsystem discovery work and from biocuration of the scientific literature.}, keywords = {Databases, Protein, Genome, Archaeal, Genome, Bacterial, Genomics, Internet, Markov chains, Molecular Sequence Annotation, Proteins, sequence alignment}, author = {Haft, Daniel H. and J. Selengut and Richter, Roland A. and Harkins, Derek and Basu, Malay K. and Beck, Erin} } @conference {38585, title = {Topological properties of chromosome conformation graphs reflect spatial proximities within chromatin}, booktitle = {Proceedings of the International Conference on Bioinformatics, Computational Biology and Biomedical Informatics}, year = {2013}, pages = {306-315}, publisher = {ACM}, organization = {ACM}, address = {Wshington DC, USA}, author = {Hao Wang and Geet Duggal and Rob Patro and Michelle Girvan and Sridhar Hannenhalli and Carl Kingsford} } @article {38526, title = {Temporal and Spatial Variability in the Distribution of Vibrio vulnificus in the Chesapeake Bay: A Hindcast Study}, journal = {EcoHealthEcoHealth}, year = {2012}, type = {10.1007/s10393-011-0736-4}, abstract = {Vibrio vulnificus, an estuarine bacterium, is the causative agent of seafood-related gastroenteritis, primary septicemia, and wound infections worldwide. It occurs as part of the normal microflora of coastal marine environments and can be isolated from water, sediment, and oysters. Hindcast prediction was undertaken to determine spatial and temporal variability in the likelihood of occurrence of V. vulnificus in surface waters of the Chesapeake Bay. Hindcast predictions were achieved by forcing a multivariate habitat suitability model with simulated sea surface temperature and salinity in the Bay for the period between 1991 and 2005 and the potential hotspots of occurrence of V. vulnificus in the Chesapeake Bay were identified. The likelihood of occurrence of V. vulnificus during high and low rainfall years was analyzed. From results of the study, it is concluded that hindcast prediction yields an improved understanding of environmental conditions associated with occurrence of V. vulnificus in the Chesapeake Bay.}, author = {Banakar, V. and Constantin de Magny, G. and Jacobs, J. and Murtugudde, R. and Huq, A. and J. Wood, R. and Rita R. Colwell} } @article {49536, title = {Transcript expression analysis of putative Trypanosoma brucei GPI-anchored surface proteins during development in the tsetse and mammalian hosts.}, volume = {6}, year = {2012}, month = {2012}, pages = {e1708}, abstract = {

Human African Trypanosomiasis is a devastating disease caused by the parasite Trypanosoma brucei. Trypanosomes live extracellularly in both the tsetse fly and the mammal. Trypanosome surface proteins can directly interact with the host environment, allowing parasites to effectively establish and maintain infections. Glycosylphosphatidylinositol (GPI) anchoring is a common posttranslational modification associated with eukaryotic surface proteins. In T. brucei, three GPI-anchored major surface proteins have been identified: variant surface glycoproteins (VSGs), procyclic acidic repetitive protein (PARP or procyclins), and brucei alanine rich proteins (BARP). The objective of this study was to select genes encoding predicted GPI-anchored proteins with unknown function(s) from the T. brucei genome and characterize the expression profile of a subset during cyclical development in the tsetse and mammalian hosts. An initial in silico screen of putative T. brucei proteins by Big PI algorithm identified 163 predicted GPI-anchored proteins, 106 of which had no known functions. Application of a second GPI-anchor prediction algorithm (FragAnchor), signal peptide and trans-membrane domain prediction software resulted in the identification of 25 putative hypothetical proteins. Eighty-one gene products with hypothetical functions were analyzed for stage-regulated expression using semi-quantitative RT-PCR. The expression of most of these genes were found to be upregulated in trypanosomes infecting tsetse salivary gland and proventriculus tissues, and 38\% were specifically expressed only by parasites infecting salivary gland tissues. Transcripts for all of the genes specifically expressed in salivary glands were also detected in mammalian infective metacyclic trypomastigotes, suggesting a possible role for these putative proteins in invasion and/or establishment processes in the mammalian host. These results represent the first large-scale report of the differential expression of unknown genes encoding predicted T. brucei surface proteins during the complete developmental cycle. This knowledge may form the foundation for the development of future novel transmission blocking strategies against metacyclic parasites.

}, keywords = {Animals, Computational Biology, Gastrointestinal Tract, Gene Expression Profiling, GPI-Linked Proteins, HUMANS, Male, Membrane Proteins, Protozoan Proteins, Real-Time Polymerase Chain Reaction, Salivary Glands, Trypanosoma brucei brucei, Trypanosomiasis, African, Tsetse Flies}, issn = {1935-2735}, doi = {10.1371/journal.pntd.0001708}, author = {Savage, Amy F and Cerqueira, Gustavo C and Regmi, Sandesh and Wu, Yineng and El Sayed, Najib M and Aksoy, Serap} } @article {38524, title = {Temperature regulation of virulence factors in the pathogen Vibrio coralliilyticus}, journal = {The ISME JournalThe ISME journal}, volume = {6}, year = {2011}, type = {10.1038/ismej.2011.154}, abstract = {Sea surface temperatures (SST) are rising because of global climate change. As a result, pathogenic Vibrio species that infect humans and marine organisms during warmer summer months are of growing concern. Coral reefs, in particular, are already experiencing unprecedented degradation worldwide due in part to infectious disease outbreaks and bleaching episodes that are exacerbated by increasing SST. For example, Vibrio coralliilyticus, a globally distributed bacterium associated with multiple coral diseases, infects corals at temperatures above 27 {\textdegree}C. The mechanisms underlying this temperature-dependent pathogenicity, however, are unknown. In this study, we identify potential virulence mechanisms using whole genome sequencing of V. coralliilyticus ATCC (American Type Culture Collection) BAA-450. Furthermore, we demonstrate direct temperature regulation of numerous virulence factors using proteomic analysis and bioassays. Virulence factors involved in motility, host degradation, secretion, antimicrobial resistance and transcriptional regulation are upregulated at the higher virulent temperature of 27 {\textdegree}C, concurrent with phenotypic changes in motility, antibiotic resistance, hemolysis, cytotoxicity and bioluminescence. These results provide evidence that temperature regulates multiple virulence mechanisms in V. coralliilyticus, independent of abundance. The ecological and biological significance of this temperature-dependent virulence response is reinforced by climate change models that predict tropical SST to consistently exceed 27 {\textdegree}C during the spring, summer and fall seasons. We propose V. coralliilyticus as a model Gram-negative bacterium to study temperature-dependent pathogenicity in Vibrio-related diseases.}, keywords = {ecophysiology, ecosystems, environmental biotechnology, geomicrobiology, ISME J, microbe interactions, microbial communities, microbial ecology, microbial engineering, microbial epidemiology, microbial genomics, microorganisms}, isbn = {1751-7362}, author = {Kimes, Nikole E. and Grim, Christopher J. and Johnson, Wesley R. and Hasan, Nur A. and Tall, Ben D. and Kothary, Mahendra H. and Kiss, Hajnalka and Munk, A. Christine and Tapia, Roxanne and Green, Lance and Detter, Chris and Bruce, David C. and Brettin, Thomas S. and Rita R. Colwell and Morris, Pamela J.} } @article {38540, title = {Transcriptional Regulation Via TF-Modifying Enzymes: An Integrative Model-Based Analysis}, journal = {Nucleic Acids ResearchNucl. Acids Res.Nucleic Acids ResearchNucl. Acids Res.}, volume = {39}, year = {2011}, type = {10.1093/nar/gkr172}, abstract = {Transcription factor activity is largely regulated through post-translational modification. Here, we report the first integrative model of transcription that includes both interactions between transcription factors and promoters, and between transcription factors and modifying enzymes. Simulations indicate that our method is robust against noise. We validated our tool on a well-studied stress response network in yeast and on a STAT1-mediated regulatory network in human B cells. Our work represents a significant step toward a comprehensive model of gene transcription.}, isbn = {0305-1048, 1362-4962}, author = {Everett, Logan J. and Jensen, Shane T. and Sridhar Hannenhalli} } @article {38522, title = {Tackling the widespread and critical impact of batch effects in high-throughput data}, journal = {Nature reviews. GeneticsNature reviews. Genetics}, volume = {11}, year = {2010}, note = {http://www.ncbi.nlm.nih.gov/pubmed/20838408?dopt=Abstract}, type = {10.1038/nrg2825}, abstract = {High-throughput technologies are widely used, for example to assay genetic variants, gene and protein expression, and epigenetic modifications. One often overlooked complication with such studies is batch effects, which occur because measurements are affected by laboratory conditions, reagent lots and personnel differences. This becomes a major problem when batch effects are correlated with an outcome of interest and lead to incorrect conclusions. Using both published studies and our own analyses, we argue that batch effects (as well as other technical and biological artefacts) are widespread and critical to address. We review experimental and computational approaches for doing so.}, keywords = {biotechnology, Computational Biology, Genomics, Oligonucleotide Array Sequence Analysis, Periodicals as Topic, Research Design, Sequence Analysis, DNA}, author = {Leek, Jeffrey T. and Scharpf, Robert B. and H{\'e}ctor Corrada Bravo and Simcha, David and Langmead, Benjamin and Johnson, W. Evan and Geman, Donald and Baggerly, Keith and Irizarry, Rafael A.} } @article {49780, title = {Three genomes from the phylum Acidobacteria provide insight into the lifestyles of these microorganisms in soils.}, journal = {Appl Environ Microbiol}, volume = {75}, year = {2009}, month = {2009 Apr}, pages = {2046-56}, abstract = {

The complete genomes of three strains from the phylum Acidobacteria were compared. Phylogenetic analysis placed them as a unique phylum. They share genomic traits with members of the Proteobacteria, the Cyanobacteria, and the Fungi. The three strains appear to be versatile heterotrophs. Genomic and culture traits indicate the use of carbon sources that span simple sugars to more complex substrates such as hemicellulose, cellulose, and chitin. The genomes encode low-specificity major facilitator superfamily transporters and high-affinity ABC transporters for sugars, suggesting that they are best suited to low-nutrient conditions. They appear capable of nitrate and nitrite reduction but not N(2) fixation or denitrification. The genomes contained numerous genes that encode siderophore receptors, but no evidence of siderophore production was found, suggesting that they may obtain iron via interaction with other microorganisms. The presence of cellulose synthesis genes and a large class of novel high-molecular-weight excreted proteins suggests potential traits for desiccation resistance, biofilm formation, and/or contribution to soil structure. Polyketide synthase and macrolide glycosylation genes suggest the production of novel antimicrobial compounds. Genes that encode a variety of novel proteins were also identified. The abundance of acidobacteria in soils worldwide and the breadth of potential carbon use by the sequenced strains suggest significant and previously unrecognized contributions to the terrestrial carbon cycle. Combining our genomic evidence with available culture traits, we postulate that cells of these isolates are long-lived, divide slowly, exhibit slow metabolic rates under low-nutrient conditions, and are well equipped to tolerate fluctuations in soil hydration.

}, keywords = {Anti-Bacterial Agents, bacteria, Biological Transport, Carbohydrate Metabolism, Cyanobacteria, DNA, Bacterial, Fungi, Genome, Bacterial, Macrolides, Molecular Sequence Data, Nitrogen, Phylogeny, Proteobacteria, Sequence Analysis, DNA, Sequence Homology, Soil Microbiology}, issn = {1098-5336}, doi = {10.1128/AEM.02294-08}, author = {Ward, Naomi L and Challacombe, Jean F and Janssen, Peter H and Henrissat, Bernard and Coutinho, Pedro M and Wu, Martin and Xie, Gary and Haft, Daniel H and Sait, Michelle and Badger, Jonathan and Barabote, Ravi D and Bradley, Brent and Brettin, Thomas S and Brinkac, Lauren M and Bruce, David and Creasy, Todd and Daugherty, Sean C and Davidsen, Tanja M and DeBoy, Robert T and Detter, J Chris and Dodson, Robert J and Durkin, A Scott and Ganapathy, Anuradha and Gwinn-Giglio, Michelle and Han, Cliff S and Khouri, Hoda and Kiss, Hajnalka and Kothari, Sagar P and Madupu, Ramana and Nelson, Karen E and Nelson, William C and Paulsen, Ian and Penn, Kevin and Ren, Qinghu and Rosovitz, M J and Selengut, Jeremy D and Shrivastava, Susmita and Sullivan, Steven A and Tapia, Roxanne and Thompson, L Sue and Watkins, Kisha L and Yang, Qi and Yu, Chunhui and Zafar, Nikhat and Zhou, Liwei and Kuske, Cheryl R} } @article {38528, title = {Three genomes from the phylum Acidobacteria provide insight into the lifestyles of these microorganisms in soils}, journal = {Applied and environmental microbiologyApplied and environmental microbiology}, volume = {75}, year = {2009}, note = {http://www.ncbi.nlm.nih.gov/pubmed/19201974?dopt=Abstract}, type = {10.1128/AEM.02294-08}, abstract = {The complete genomes of three strains from the phylum Acidobacteria were compared. Phylogenetic analysis placed them as a unique phylum. They share genomic traits with members of the Proteobacteria, the Cyanobacteria, and the Fungi. The three strains appear to be versatile heterotrophs. Genomic and culture traits indicate the use of carbon sources that span simple sugars to more complex substrates such as hemicellulose, cellulose, and chitin. The genomes encode low-specificity major facilitator superfamily transporters and high-affinity ABC transporters for sugars, suggesting that they are best suited to low-nutrient conditions. They appear capable of nitrate and nitrite reduction but not N(2) fixation or denitrification. The genomes contained numerous genes that encode siderophore receptors, but no evidence of siderophore production was found, suggesting that they may obtain iron via interaction with other microorganisms. The presence of cellulose synthesis genes and a large class of novel high-molecular-weight excreted proteins suggests potential traits for desiccation resistance, biofilm formation, and/or contribution to soil structure. Polyketide synthase and macrolide glycosylation genes suggest the production of novel antimicrobial compounds. Genes that encode a variety of novel proteins were also identified. The abundance of acidobacteria in soils worldwide and the breadth of potential carbon use by the sequenced strains suggest significant and previously unrecognized contributions to the terrestrial carbon cycle. Combining our genomic evidence with available culture traits, we postulate that cells of these isolates are long-lived, divide slowly, exhibit slow metabolic rates under low-nutrient conditions, and are well equipped to tolerate fluctuations in soil hydration.}, keywords = {Anti-Bacterial Agents, bacteria, Biological Transport, Carbohydrate Metabolism, Cyanobacteria, DNA, Bacterial, Fungi, Genome, Bacterial, Macrolides, Molecular Sequence Data, Nitrogen, Phylogeny, Proteobacteria, Sequence Analysis, DNA, Sequence Homology, Soil Microbiology}, author = {Ward, Naomi L. and Challacombe, Jean F. and Janssen, Peter H. and Henrissat, Bernard and Coutinho, Pedro M. and Wu, Martin and Xie, Gary and Haft, Daniel H. and Sait, Michelle and Badger, Jonathan and Barabote, Ravi D. and Bradley, Brent and Brettin, Thomas S. and Brinkac, Lauren M. and Bruce, David and Creasy, Todd and Daugherty, Sean C. and Davidsen, Tanja M. and DeBoy, Robert T. and Detter, J. Chris and Dodson, Robert J. and Durkin, A. Scott and Ganapathy, Anuradha and Gwinn-Giglio, Michelle and Han, Cliff S. and Khouri, Hoda and Kiss, Hajnalka and Kothari, Sagar P. and Madupu, Ramana and Nelson, Karen E. and Nelson, William C. and Paulsen, Ian and Penn, Kevin and Ren, Qinghu and Rosovitz, M. J. and J. Selengut and Shrivastava, Susmita and Sullivan, Steven A. and Tapia, Roxanne and Thompson, L. Sue and Watkins, Kisha L. and Yang, Qi and Yu, Chunhui and Zafar, Nikhat and Zhou, Liwei and Kuske, Cheryl R.} } @article {38533, title = {Toward reconstructing the evolution of advanced moths and butterflies (Lepidoptera: Ditrysia): an initial molecular study}, journal = {BMC Evol BiolBMC Evol Biol}, volume = {9}, year = {2009}, type = {10.1186/1471-2148-9-280}, abstract = {BACKGROUND: In the mega-diverse insect order Lepidoptera (butterflies and moths; 165,000 described species), deeper relationships are little understood within the clade Ditrysia, to which 98\% of the species belong. To begin addressing this problem, we tested the ability of five protein-coding nuclear genes (6.7 kb total), and character subsets therein, to resolve relationships among 123 species representing 27 (of 33) superfamilies and 55 (of 100) families of Ditrysia under maximum likelihood analysis. RESULTS: Our trees show broad concordance with previous morphological hypotheses of ditrysian phylogeny, although most relationships among superfamilies are weakly supported. There are also notable surprises, such as a consistently closer relationship of Pyraloidea than of butterflies to most Macrolepidoptera. Monophyly is significantly rejected by one or more character sets for the putative clades Macrolepidoptera as currently defined (P < 0.05) and Macrolepidoptera excluding Noctuoidea and Bombycoidea sensu lato (P < or = 0.005), and nearly so for the superfamily Drepanoidea as currently defined (P < 0.08). Superfamilies are typically recovered or nearly so, but usually without strong support. Relationships within superfamilies and families, however, are often robustly resolved. We provide some of the first strong molecular evidence on deeper splits within Pyraloidea, Tortricoidea, Geometroidea, Noctuoidea and others.Separate analyses of mostly synonymous versus non-synonymous character sets revealed notable differences (though not strong conflict), including a marked influence of compositional heterogeneity on apparent signal in the third codon position (nt3). As available model partitioning methods cannot correct for this variation, we assessed overall phylogeny resolution through separate examination of trees from each character set. Exploration of "tree space" with GARLI, using grid computing, showed that hundreds of searches are typically needed to find the best-feasible phylogeny estimate for these data. CONCLUSION: Our results (a) corroborate the broad outlines of the current working phylogenetic hypothesis for Ditrysia, (b) demonstrate that some prominent features of that hypothesis, including the position of the butterflies, need revision, and (c) resolve the majority of family and subfamily relationships within superfamilies as thus far sampled. Much further gene and taxon sampling will be needed, however, to strongly resolve individual deeper nodes.}, author = {Regier, J. C. and Zwick, A. and Michael P. Cummings and Kawahara, A. Y. and Cho, S. and Weller, S. and Roe, A. and Baixeras, J. and Brown, J. W. and Parr, C. and Davis, D. R. and Epstein, M. and Hallwachs, W. and Hausmann, A. and Janzen, D. H. and Kitching, I. J. and Solis, M. A. and Yen, S. H. and Adam L. Bazinet and Mitter, C.} } @article {49675, title = {Two alternatively spliced isoforms of the Arabidopsis SR45 protein have distinct roles during normal plant development.}, journal = {Plant Physiol}, volume = {150}, year = {2009}, month = {2009 Jul}, pages = {1450-8}, abstract = {

The serine-arginine-rich (SR) proteins constitute a conserved family of pre-mRNA splicing factors. In Arabidopsis (Arabidopsis thaliana), they are encoded by 19 genes, most of which are themselves alternatively spliced. In the case of SR45, the use of alternative 3{\textquoteright} splice sites 21 nucleotides apart generates two alternatively spliced isoforms. Isoform 1 (SR45.1) has an insertion relative to isoform 2 (SR45.2) that replaces a single arginine with eight amino acids (TSPQRKTG). The biological implications of SR45 alternative splicing have been unclear. A previously described loss-of-function mutant affecting both isoforms, sr45-1, shows several developmental defects, including defects in petal development and root growth. We found that the SR45 promoter is highly active in regions with actively growing and dividing cells. We also tested the ability of each SR45 isoform to complement the sr45-1 mutant by overexpression of isoform-specific green fluorescent protein (GFP) fusion proteins. As expected, transgenic plants overexpressing either isoform displayed both nuclear speckles and GFP fluorescence throughout the nucleoplasm. We found that SR45.1-GFP complements the flower petal phenotype, but not the root growth phenotype. Conversely, SR45.2-GFP complements root growth but not floral morphology. Mutation of a predicted phosphorylation site within the alternatively spliced segment, SR45.1-S219A-GFP, does not affect complementation. However, a double mutation affecting both serine-219 and the adjacent threonine-218 (SR45.1-T218A + S219A-GFP) behaves like isoform 2, complementing the root but not the floral phenotype. In conclusion, our study provides evidence that the two alternatively spliced isoforms of SR45 have distinct biological functions.

}, keywords = {Alternative Splicing, Amino Acid Sequence, Arabidopsis, Arabidopsis Proteins, Carrier Proteins, Flowers, Molecular Sequence Data, Mutation, Plant Roots, Protein Isoforms, Ribonucleoproteins, RNA-Binding Proteins, sequence alignment}, issn = {0032-0889}, doi = {10.1104/pp.109.138180}, author = {Zhang, Xiao-Ning and Mount, Stephen M} } @article {38541, title = {Transesterification activity of a novel lipase from Acinetobacter venetianus RAG-1}, journal = {Antonie van LeeuwenhoekAntonie van Leeuwenhoek}, volume = {94}, year = {2008}, type = {10.1007/s10482-008-9276-5}, abstract = {Transesterification activity and the industrial potential of a novel lipase prepared from Acinetobacter ventiatus RAG-1 were evaluated. Purified lipase samples were dialyzed against pH 9.0 buffer in a single optimization step prior to lyophilization. The enzyme and organic phase were pre-equilibrated (separately) to the same thermodynamic water activities (a w) ranging from a w 0.33 to 0.97. Production of 1-octyl butyrate by lipase-catalyzed transesterification of vinyl butyrate with 1-octanol in hexane was monitored by gas chromatography. Production of 1-octyl butyrate and initial rate of reaction depended on water activity. Product synthesis and rate of transesterification increased sharply with increase from a w 0.33 to 0.55. Highest product concentration (218 mM) and rate of reaction (18.7 μmol h-1 {\textperiodcentered} 10 μg protein) were measured at a w 0.86. Transesterification activity in hexane represented 32\% of comparable hydrolytic activity in aqueous buffer.}, author = {Snellman, E. A. and Rita R. Colwell} } @article {38552, title = {A Tutorial of the Poisson Random Field Model in Population Genetics}, journal = {Advances in BioinformaticsAdvances in Bioinformatics}, volume = {2008}, year = {2008}, type = {10.1155/2008/257864}, abstract = {Population genetics is the study of allele frequency changes driven by various evolutionary forces such as mutation, natural selection, and random genetic drift. Although natural selection is widely recognized as a bona-fide phenomenon, the extent to which it drives evolution continues to remain unclear and controversial. Various qualitative techniques, or so-called {\textquotedblleft}tests of neutrality{\textquotedblright}, have been introduced to detect signatures of natural selection. A decade and a half ago, Stanley Sawyer and Daniel Hartl provided a mathematical framework, referred to as the Poisson random field (PRF), with which to determine quantitatively the intensity of selection on a particular gene or genomic region. The recent availability of large-scale genetic polymorphism data has sparked widespread interest in genome-wide investigations of natural selection. To that end, the original PRF model is of particular interest for geneticists and evolutionary genomicists. In this article, we will provide a tutorial of the mathematical derivation of the original Sawyer and Hartl PRF model.}, isbn = {1687-8027, 1687-8035}, author = {Sethupathy, Praveen and Sridhar Hannenhalli} } @article {38530, title = {TIGRFAMs and Genome Properties: tools for the assignment of molecular function and biological process in prokaryotic genomes}, journal = {Nucleic acids researchNucleic Acids Research}, volume = {35}, year = {2007}, note = {http://www.ncbi.nlm.nih.gov/pubmed/17151080?dopt=Abstract}, type = {10.1093/nar/gkl1043}, abstract = {TIGRFAMs is a collection of protein family definitions built to aid in high-throughput annotation of specific protein functions. Each family is based on a hidden Markov model (HMM), where both cutoff scores and membership in the seed alignment are chosen so that the HMMs can classify numerous proteins according to their specific molecular functions. Most TIGRFAMs models describe {\textquoteright}equivalog{\textquoteright} families, where both orthology and lateral gene transfer may be part of the evolutionary history, but where a single molecular function has been conserved. The Genome Properties system contains a queriable set of metabolic reconstructions, genome metrics and extractions of information from the scientific literature. Its genome-by-genome assertions of whether or not specific structures, pathways or systems are present provide high-level conceptual descriptions of genomic content. These assertions enable comparative genomics, provide a meaningful biological context to aid in manual annotation, support assignments of Gene Ontology (GO) biological process terms and help validate HMM-based predictions of protein function. The Genome Properties system is particularly useful as a generator of phylogenetic profiles, through which new protein family functions may be discovered. The TIGRFAMs and Genome Properties systems can be accessed at http://www.tigr.org/TIGRFAMs and http://www.tigr.org/Genome_Properties.}, keywords = {Archaeal Proteins, Bacterial Proteins, Databases, Protein, Genome, Bacterial, Genomics, Internet, Phylogeny, software, User-Computer Interface}, author = {J. Selengut and Haft, Daniel H. and Davidsen, Tanja and Ganapathy, Anurhada and Gwinn-Giglio, Michelle and Nelson, William C. and Richter, R. Alexander and White, Owen} } @article {38547, title = {TREMOR{\textemdash}a tool for retrieving transcriptional modules by incorporating motif covariance}, journal = {Nucleic acids researchNucleic Acids Research}, volume = {35}, year = {2007}, publisher = {Oxford Univ Press}, author = {Singh, L. N. and Wang, L. S. and Sridhar Hannenhalli} } @article {38535, title = {Toxigenic Vibrio Cholerae in the Aquatic Environment of Mathbaria, Bangladesh}, journal = {Applied and Environmental MicrobiologyAppl. Environ. Microbiol.Applied and Environmental MicrobiologyAppl. Environ. Microbiol.}, volume = {72}, year = {2006}, type = {10.1128/AEM.72.4.2849-2855.2006}, abstract = {Toxigenic Vibrio cholerae, rarely isolated from the aquatic environment between cholera epidemics, can be detected in what is now understood to be a dormant stage, i.e., viable but nonculturable when standard bacteriological methods are used. In the research reported here, biofilms have proved to be a source of culturable V. cholerae, even in nonepidemic periods. Biweekly environmental surveillance for V. cholerae was carried out in Mathbaria, an area of cholera endemicity adjacent to the Bay of Bengal, with the focus on V. cholerae O1 and O139 Bengal. A total of 297 samples of water, phytoplankton, and zooplankton were collected between March and December 2004, yielding eight V. cholerae O1 and four O139 Bengal isolates. A combination of culture methods, multiplex-PCR, and direct fluorescent antibody (DFA) counting revealed the Mathbaria aquatic environment to be a reservoir for V. cholerae O1 and O139 Bengal. DFA results showed significant clumping of the bacteria during the interepidemic period for cholera, and the fluorescent micrographs revealed large numbers of V. cholerae O1 in thin films of exopolysaccharides (biofilm). A similar clumping of V. cholerae O1 was also observed in samples collected from Matlab, Bangladesh, where cholera also is endemic. Thus, the results of the study provided in situ evidence for V. cholerae O1 and O139 in the aquatic environment, predominantly as viable but nonculturable cells and culturable cells in biofilm consortia. The biofilm community is concluded to be an additional reservoir of cholera bacteria in the aquatic environment between seasonal epidemics of cholera in Bangladesh.}, isbn = {0099-2240, 1098-5336}, author = {Alam, Munirul and Sultana, Marzia and Nair, G. Balakrish and Sack, R. Bradley and Sack, David A. and Siddique, A. K. and Ali, Afsar and Huq, Anwar and Rita R. Colwell} } @article {38537, title = {Transcriptional Genomics Associates FOX Transcription Factors With Human Heart Failure}, journal = {CirculationCirculation}, volume = {114}, year = {2006}, type = {10.1161/CIRCULATIONAHA.106.632430}, abstract = {Background{\textemdash} Specific transcription factors (TFs) modulate cardiac gene expression in murine models of heart failure, but their relevance in human subjects remains untested. We developed and applied a computational approach called transcriptional genomics to test the hypothesis that a discrete set of cardiac TFs is associated with human heart failure.Methods and Results{\textemdash} RNA isolates from failing (n=196) and nonfailing (n=16) human hearts were hybridized with Affymetrix HU133A arrays, and differentially expressed heart failure genes were determined. TF binding sites overrepresented in the -5-kb promoter sequences of these heart failure genes were then determined with the use of public genome sequence databases. Binding sites for TFs identified in murine heart failure models (MEF2, NKX, NF-AT, and GATA) were significantly overrepresented in promoters of human heart failure genes (P<0.002; false discovery rate 2\% to 4\%). In addition, binding sites for FOX TFs showed substantial overrepresentation in both advanced human and early murine heart failure (P<0.002 and false discovery rate <4\% for each). A role for FOX TFs was supported further by expression of FOXC1, C2, P1, P4, and O1A in failing human cardiac myocytes at levels similar to established hypertrophic TFs and by abundant FOXP1 protein in failing human cardiac myocyte nuclei.Conclusions{\textemdash} Our results provide the first evidence that specific TFs identified in murine models (MEF2, NKX, NFAT, and GATA) are associated with human heart failure. Moreover, these data implicate specific members of the FOX family of TFs (FOXC1, C2, P1, P4, and O1A) not previously suggested in heart failure pathogenesis. These findings provide a crucial link between animal models and human disease and suggest a specific role for FOX signaling in modulating the hypertrophic response of the heart to stress in humans.}, author = {Sridhar Hannenhalli and Putt, Mary E. and Gilmore, Joan M. and Wang, Junwen and Parmacek, Michael S. and Epstein, Jonathan A. and Morrisey, Edward E. and Margulies, Kenneth B. and Cappola, Thomas P.} } @article {49639, title = {The Trypanosoma cruzi L1Tc and NARTc non-LTR retrotransposons show relative site specificity for insertion.}, journal = {Mol Biol Evol}, volume = {23}, year = {2006}, month = {2006 Feb}, pages = {411-20}, abstract = {

The trypanosomatid protozoan Trypanosoma cruzi contains long autonomous (L1Tc) and short nonautonomous (NARTc) non-long terminal repeat retrotransposons. NARTc (0.25 kb) probably derived from L1Tc (4.9 kb) by 3{\textquoteright}-deletion. It has been proposed that their apparent random distribution in the genome is related to the L1Tc-encoded apurinic/apyrimidinic endonuclease (APE) activity, which repairs modified residues. To address this question we used the T. cruzi (CL-Brener strain) genome data to analyze the distribution of all the L1Tc/NARTc elements present in contigs larger than 10 kb. This data set, which represents 0.91x sequence coverage of the haploid nuclear genome ( approximately 55 Mb), contains 419 elements, including 112 full-length L1Tc elements (14 of which are potentially functional) and 84 full-length NARTc. Approximately half of the full-length elements are flanked by a target site duplication, most of them (87\%) are 12 bp long. Statistical analyses of sequences flanking the full-length elements show the same highly conserved pattern upstream of both the L1Tc and NARTc retrotransposons. The two most conserved residues are a guanine and an adenine, which flank the site where first-strand cleavage is performed by the element-encoded endonuclease activity. This analysis clearly indicates that the L1Tc and NARTc elements display relative site specificity for insertion, which suggests that the APE activity is not responsible for first-strand cleavage of the target site.

}, keywords = {Animals, DNA, Protozoan, DNA-(Apurinic or Apyrimidinic Site) Lyase, Mutagenesis, Insertional, Retroelements, Sequence Deletion, Trypanosoma cruzi}, issn = {0737-4038}, doi = {10.1093/molbev/msj046}, author = {Bringaud, Frederic and Bartholomeu, Daniella C and Blandin, Ga{\"e}lle and Delcher, Arthur and Baltz, Th{\'e}o and el-Sayed, Najib M A and Ghedin, Elodie} } @article {38549, title = {The Trypanosoma cruzi L1Tc and NARTc non-LTR retrotransposons show relative site specificity for insertion}, journal = {Molecular biology and evolutionMolecular biology and evolution}, volume = {23}, year = {2006}, author = {Bringaud, F. and Bartholomeu, D. C. and Blandin, G. and Delcher, A. and Baltz, T. and Najib M. El-Sayed and Ghedin, E.} } @article {38550, title = {Trypanosoma cruzi mitochondrial maxicircles display species- and strain-specific variation and a conserved element in the non-coding region}, journal = {BMC GenomicsBMC Genomics}, volume = {7}, year = {2006}, type = {10.1186/1471-2164-7-60}, abstract = {BACKGROUND:The mitochondrial DNA of kinetoplastid flagellates is distinctive in the eukaryotic world due to its massive size, complex form and large sequence content. Comprised of catenated maxicircles that contain rRNA and protein-coding genes and thousands of heterogeneous minicircles encoding small guide RNAs, the kinetoplast network has evolved along with an extreme form of mRNA processing in the form of uridine insertion and deletion RNA editing. Many maxicircle-encoded mRNAs cannot be translated without this post-transcriptional sequence modification.RESULTS:We present the complete sequence and annotation of the Trypanosoma cruzi maxicircles for the CL Brener and Esmeraldo strains. Gene order is syntenic with Trypanosoma brucei and Leishmania tarentolae maxicircles. The non-coding components have strain-specific repetitive regions and a variable region that is unique for each strain with the exception of a conserved sequence element that may serve as an origin of replication, but shows no sequence identity with L. tarentolae or T. brucei. Alternative assemblies of the variable region demonstrate intra-strain heterogeneity of the maxicircle population. The extent of mRNA editing required for particular genes approximates that seen in T. brucei. Extensively edited genes were more divergent among the genera than non-edited and rRNA genes. Esmeraldo contains a unique 236-bp deletion that removes the 5{\textquoteright}-ends of ND4 and CR4 and the intergenic region. Esmeraldo shows additional insertions and deletions outside of areas edited in other species in ND5, MURF1, and MURF2, while CL Brener has a distinct insertion in MURF2.CONCLUSION:The CL Brener and Esmeraldo maxicircles represent two of three previously defined maxicircle clades and promise utility as taxonomic markers. Restoration of the disrupted reading frames might be accomplished by strain-specific RNA editing. Elements in the non-coding region may be important for replication, transcription, and anchoring of the maxicircle within the kinetoplast network.}, isbn = {1471-2164}, author = {Westenberger, Scott and Cerqueira, Gustavo and Najib M. El-Sayed and Zingales, Bianca and Campbell, David and Sturm, Nancy} } @article {49640, title = {Trypanosoma cruzi mitochondrial maxicircles display species- and strain-specific variation and a conserved element in the non-coding region.}, journal = {BMC Genomics}, volume = {7}, year = {2006}, month = {2006}, pages = {60}, abstract = {

BACKGROUND: The mitochondrial DNA of kinetoplastid flagellates is distinctive in the eukaryotic world due to its massive size, complex form and large sequence content. Comprised of catenated maxicircles that contain rRNA and protein-coding genes and thousands of heterogeneous minicircles encoding small guide RNAs, the kinetoplast network has evolved along with an extreme form of mRNA processing in the form of uridine insertion and deletion RNA editing. Many maxicircle-encoded mRNAs cannot be translated without this post-transcriptional sequence modification.

RESULTS: We present the complete sequence and annotation of the Trypanosoma cruzi maxicircles for the CL Brener and Esmeraldo strains. Gene order is syntenic with Trypanosoma brucei and Leishmania tarentolae maxicircles. The non-coding components have strain-specific repetitive regions and a variable region that is unique for each strain with the exception of a conserved sequence element that may serve as an origin of replication, but shows no sequence identity with L. tarentolae or T. brucei. Alternative assemblies of the variable region demonstrate intra-strain heterogeneity of the maxicircle population. The extent of mRNA editing required for particular genes approximates that seen in T. brucei. Extensively edited genes were more divergent among the genera than non-edited and rRNA genes. Esmeraldo contains a unique 236-bp deletion that removes the 5{\textquoteright}-ends of ND4 and CR4 and the intergenic region. Esmeraldo shows additional insertions and deletions outside of areas edited in other species in ND5, MURF1, and MURF2, while CL Brener has a distinct insertion in MURF2.

CONCLUSION: The CL Brener and Esmeraldo maxicircles represent two of three previously defined maxicircle clades and promise utility as taxonomic markers. Restoration of the disrupted reading frames might be accomplished by strain-specific RNA editing. Elements in the non-coding region may be important for replication, transcription, and anchoring of the maxicircle within the kinetoplast network.

}, keywords = {Amino Acid Sequence, Animals, Animals, Inbred Strains, Base Composition, Conserved Sequence, DNA, Kinetoplast, Frameshifting, Ribosomal, Gene Deletion, Gene Order, Genetic Variation, Leishmania, Models, Biological, Molecular Sequence Data, Muscle Proteins, NADH Dehydrogenase, Open Reading Frames, Regulatory Elements, Transcriptional, RNA Editing, Sequence Homology, Amino Acid, Species Specificity, Trypanosoma brucei brucei, Trypanosoma cruzi, Ubiquitin-Protein Ligases, Untranslated Regions}, issn = {1471-2164}, doi = {10.1186/1471-2164-7-60}, author = {Westenberger, Scott J and Cerqueira, Gustavo C and El-Sayed, Najib M and Zingales, Bianca and Campbell, David A and Sturm, Nancy R} } @article {49636, title = {Telomere and subtelomere of Trypanosoma cruzi chromosomes are enriched in (pseudo)genes of retrotransposon hot spot and trans-sialidase-like gene families: the origins of T. cruzi telomeres.}, journal = {Gene}, volume = {346}, year = {2005}, month = {2005 Feb 14}, pages = {153-61}, abstract = {

Here, we sequenced two large telomeric regions obtained from the pathogen protozoan Trypanosoma cruzi. These sequences, together with in silico assembled contigs, allowed us to establish the general features of telomeres and subtelomeres of this parasite. Our findings can be summarized as follows: We confirmed the presence of two types of telomeric ends; subtelomeric regions appeared to be enriched in (pseudo)genes of RHS (retrotransposon hot spot), TS (trans-sialidase)-like proteins, and putative surface protein DGF-1 (dispersed gene family-1). Sequence analysis of the ts-like genes located at the telomeres suggested that T. cruzi chromosomal ends could have been the site for generation of new gp85 variants, an important adhesin molecule involved in the invasion of mammalian cells by T. cruzi. Finally, a mechanism for generation of T. cruzi telomere by chromosome breakage and telomere healing is proposed.

}, keywords = {Amino Acid Sequence, Animals, Base Sequence, Chromosomes, Chromosomes, Artificial, Bacterial, DNA, Protozoan, Genes, Protozoan, Glycoproteins, Molecular Sequence Data, Multigene Family, Neuraminidase, Pseudogenes, Retroelements, Sequence Homology, Amino Acid, Sequence Homology, Nucleic Acid, Telomere, Trypanosoma cruzi}, issn = {0378-1119}, doi = {10.1016/j.gene.2004.10.014}, author = {Kim, Dong and Chiurillo, Miguel Angel and El-Sayed, Najib and Jones, Kristin and Santos, M{\'a}rcia R M and Porcile, Patricio E and Andersson, Bj{\"o}rn and Myler, Peter and da Silveira, Jose Franco and Ram{\'\i}rez, Jos{\'e} Luis} } @article {38525, title = {Temperature-Driven Campylobacter Seasonality in England and Wales}, journal = {Applied and Environmental MicrobiologyAppl. Environ. Microbiol.Applied and Environmental MicrobiologyAppl. Environ. Microbiol.}, volume = {71}, year = {2005}, type = {10.1128/AEM.71.1.85-92.2005}, abstract = {Campylobacter incidence in England and Wales between 1990 and 1999 was examined in conjunction with weather conditions. Over the 10-year interval, the average annual rate was determined to be 78.4 {\textpm} 15.0 cases per 100,000, with an upward trend. Rates were higher in males than in females, regardless of age, and highest in children less than 5 years old. Major regional differences were detected, with the highest rates in Wales and the southwest and the lowest in the southeast. The disease displayed a seasonal pattern, and increased campylobacter rates were found to be correlated with temperature. The most marked seasonal effect was observed for children under the age of 5. The seasonal pattern of campylobacter infections indicated a linkage with environmental factors rather than food sources. Therefore, public health interventions should not be restricted to food-borne approaches, and the epidemiology of the seasonal peak in human campylobacter infections may best be understood through studies in young children.}, isbn = {0099-2240, 1098-5336}, author = {Louis, Val{\'e}rie R. and Gillespie, Iain A. and O{\textquoteright}Brien, Sarah J. and Russek-Cohen, Estelle and Pearson, Andrew D. and Rita R. Colwell} } @article {49637, title = {Transcriptional profiling of the hyperthermophilic methanarchaeon Methanococcus jannaschii in response to lethal heat and non-lethal cold shock.}, journal = {Environ Microbiol}, volume = {7}, year = {2005}, month = {2005 Jun}, pages = {789-97}, abstract = {

Temperature shock of the hyperthermophilic methanarchaeon Methanococcus jannaschii from its optimal growth temperature of 85 degrees C to 65 degrees C and 95 degrees C resulted in different transcriptional responses characteristic of both the direction of shock (heat or cold shock) and whether the shock was lethal. Specific outcomes of lethal heat shock to 95 degrees C included upregulation of genes encoding chaperones, and downregulation of genes encoding subunits of the H+ transporting ATP synthase. A gene encoding an alpha subunit of a putative prefoldin was also upregulated, which may comprise a novel element in the protein processing pathway in M. jannaschii. Very different responses were observed upon cold shock to 65 degrees C. These included upregulation of a gene encoding an RNA helicase and other genes involved in transcription and translation, and upregulation of genes coding for proteases and transport proteins. Also upregulated was a gene that codes for an 18 kDa FKBP-type PPIase, which may facilitate protein folding at low temperatures. Transcriptional profiling also revealed several hypothetical proteins that respond to temperature stress conditions.

}, keywords = {Adaptation, Physiological, Archaeal Proteins, Cold Temperature, Gene Expression Profiling, Gene Expression Regulation, Archaeal, Heat-Shock Proteins, Hot Temperature, Methanococcus, Temperature, Transcription, Genetic}, issn = {1462-2912}, doi = {10.1111/j.1462-2920.2005.00751.x}, author = {Boonyaratanakornkit, Boonchai B and Simpson, Anjana J and Whitehead, Timothy A and Fraser, Claire M and el-Sayed, Najib M A and Clark, Douglas S} } @article {38538, title = {Transcriptional profiling of the hyperthermophilic methanarchaeon Methanococcus jannaschii in response to lethal heat and non-lethal cold shock}, journal = {Environmental MicrobiologyEnvironmental Microbiology}, volume = {7}, year = {2005}, type = {10.1111/j.1462-2920.2005.00751.x}, abstract = {Temperature shock of the hyperthermophilic methanarchaeon Methanococcus jannaschii from its optimal growth temperature of 85{\textdegree}C to 65{\textdegree}C and 95{\textdegree}C resulted in different transcriptional responses characteristic of both the direction of shock (heat or cold shock) and whether the shock was lethal. Specific outcomes of lethal heat shock to 95{\textdegree}C included upregulation of genes encoding chaperones, and downregulation of genes encoding subunits of the H+ transporting ATP synthase. A gene encoding an α subunit of a putative prefoldin was also upregulated, which may comprise a novel element in the protein processing pathway in M. jannaschii. Very different responses were observed upon cold shock to 65{\textdegree}C. These included upregulation of a gene encoding an RNA helicase and other genes involved in transcription and translation, and upregulation of genes coding for proteases and transport proteins. Also upregulated was a gene that codes for an 18~kDa FKBP-type PPIase, which may facilitate protein folding at low temperatures. Transcriptional profiling also revealed several hypothetical proteins that respond to temperature stress conditions.}, isbn = {1462-2920}, author = {Boonyaratanakornkit, Boonchai B. and Simpson, Anjana J. and Whitehead, Timothy A. and Fraser, Claire M. and Najib M. El-Sayed and Clark, Douglas S.} } @inbook {38523, title = {A Tangled Bank: Reflections on the Tree of Life and Human Health}, booktitle = {Assembling the Tree of LifeAssembling the Tree of Life}, year = {2004}, publisher = {Oxford University Press}, organization = {Oxford University Press}, isbn = {9780195172348}, author = {Rita R. Colwell} } @article {38531, title = {The TIGRFAMs database of protein families}, journal = {Nucleic acids researchNucleic Acids Research}, volume = {31}, year = {2003}, note = {http://www.ncbi.nlm.nih.gov/pubmed/12520025?dopt=Abstract}, abstract = {TIGRFAMs is a collection of manually curated protein families consisting of hidden Markov models (HMMs), multiple sequence alignments, commentary, Gene Ontology (GO) assignments, literature references and pointers to related TIGRFAMs, Pfam and InterPro models. These models are designed to support both automated and manually curated annotation of genomes. TIGRFAMs contains models of full-length proteins and shorter regions at the levels of superfamilies, subfamilies and equivalogs, where equivalogs are sets of homologous proteins conserved with respect to function since their last common ancestor. The scope of each model is set by raising or lowering cutoff scores and choosing members of the seed alignment to group proteins sharing specific function (equivalog) or more general properties. The overall goal is to provide information with maximum utility for the annotation process. TIGRFAMs is thus complementary to Pfam, whose models typically achieve broad coverage across distant homologs but end at the boundaries of conserved structural domains. The database currently contains over 1600 protein families. TIGRFAMs is available for searching or downloading at www.tigr.org/TIGRFAMs.}, keywords = {Animals, Databases, Protein, Markov chains, Mixed Function Oxygenases, Phylogeny, Proteins, Pyruvate Carboxylase, Sequence Homology, Amino Acid}, author = {Haft, Daniel H. and J. Selengut and White, Owen} } @article {38536, title = {The transcription factor Eyes absent is a protein tyrosine phosphatase}, journal = {NatureNature}, volume = {426}, year = {2003}, note = {http://www.ncbi.nlm.nih.gov/pubmed/14628053?dopt=Abstract}, type = {10.1038/nature02097}, abstract = {Post-translational modifications provide sensitive and flexible mechanisms to dynamically modulate protein function in response to specific signalling inputs. In the case of transcription factors, changes in phosphorylation state can influence protein stability, conformation, subcellular localization, cofactor interactions, transactivation potential and transcriptional output. Here we show that the evolutionarily conserved transcription factor Eyes absent (Eya) belongs to the phosphatase subgroup of the haloacid dehalogenase (HAD) superfamily, and propose a function for it as a non-thiol-based protein tyrosine phosphatase. Experiments performed in cultured Drosophila cells and in vitro indicate that Eyes absent has intrinsic protein tyrosine phosphatase activity and can autocatalytically dephosphorylate itself. Confirming the biological significance of this function, mutations that disrupt the phosphatase active site severely compromise the ability of Eyes absent to promote eye specification and development in Drosophila. Given the functional importance of phosphorylation-dependent modulation of transcription factor activity, this evidence for a nuclear transcriptional coactivator with intrinsic phosphatase activity suggests an unanticipated method of fine-tuning transcriptional regulation.}, keywords = {Amino Acid Motifs, Amino Acid Sequence, Animals, Antibodies, Phospho-Specific, Drosophila melanogaster, Drosophila Proteins, Embryonic Induction, eye, Eye Proteins, Gene Expression Regulation, Kinetics, Mice, Models, Molecular, Molecular Sequence Data, Mutation, Phosphorylation, Protein Conformation, Protein Tyrosine Phosphatases, Substrate Specificity, Transcription Factors}, author = {Tootle, Tina L. and Silver, Serena J. and Davies, Erin L. and Newman, Victoria and Latek, Robert R. and Mills, Ishara A. and J. Selengut and Parlikar, Beth E. W. and Rebay, Ilaria} } @article {38539, title = {Transcriptional regulation of protein complexes and biological pathways}, journal = {Mammalian GenomeMammalian Genome}, volume = {14}, year = {2003}, abstract = {The cis-element profile (or cis-profile) of a gene refers to the collection of transcription factor binding sites (TFBS) regulating the transcription of the gene. Underlying the various published studies that attempt to discover cis-elements in the vicinity of co-expressed genes via pattern detection algorithms, there is an implicit assumption that a correlation exists between co-expressed genes and their cis-profiles. In this study, we show that the cis-similarity, defined as the proportion of shared TFBS between two cis-element profiles, is higher for functionally linked interacting proteins as well as for members of a signal transduction pathway. A similar analysis of the enzymes catalyzing the conversion of adjacent substrates to products in a collection of metabolic pathways, did not reveal higher cis-similarity. The analysis is based on three distinct sources of publicly available data, namely, 1) the BIND database of interacting proteins, 2) known interactions in NMDAR protein complex, 3) the apoptosis pathway and nine pathways related to metabolism of cofactors and vitamins all from KEGG. Additionally, we analyze the cis-element profiles of all the genes in the glutamate receptor (GR) sub-complex of NMDAR complex to detect a set of cis-elements that occur adjacent to a majority of the genes. We show that most of the corresponding transcription factors are known to be involved in GR regulation by comparing our findings with the published biomedical literature. In addition, we were able to detect transcripts whose gene products associate with GR by searching for transcripts that share the same regulatory signals as those detected for GR. This suggests a novel computational methodology for constructing high-order gene regulatory models and detecting co-regulated gene products.}, isbn = {0938-8990}, author = {Sridhar Hannenhalli and Levy, Samuel} } @article {38551, title = {Trypanosoma cruzi: RNA structure and post-transcriptional control of tubulin gene expression}, journal = {Experimental ParasitologyExperimental Parasitology}, volume = {102}, year = {2002}, type = {16/S0014-4894(03)00034-1}, abstract = {Changes in tubulin expression are among the biochemical and morphological adaptations that occur during the life cycle of Trypanosomatids. To investigate the mechanism responsible for the differential accumulation of tubulin mRNAs in Trypanosoma cruzi, we determine the sequences of [alpha]- and [beta]-tubulin transcripts and analyzed their expression during the life cycle of the parasite. Two [beta]-tubulin mRNAs of 1.9 and 2.3~kb were found to differ mainly by an additional 369 nucleotides at the end of the 3{\textquoteright} untranslated region (UTR). Although their transcription rates are similar in epimastigotes and amastigotes, [alpha]- and [beta]-tubulin transcripts are 3- to 6-fold more abundant in epimastigotes than in trypomastigotes and amastigotes. Accordingly, the half-lives of [alpha]- and [beta]-tubulin mRNAs are significantly higher in epimastigotes than in amastigotes. Transient transfection experiments indicated that positive regulatory elements occur in the 3{\textquoteright} UTR plus downstream intergenic region of the [alpha]-tubulin gene and that both positive and negative elements occur in the equivalent regions of the [beta]-tubulin gene.Index Descriptions and Abbreviations: Kinetoplastida; Trypanosoma cruzi; tubulin; gene regulation; PCR, polymerase chain reaction; UTR, untranslated region; IR, intergenic region; SL, spliced leader; BAC, bacterial artificial chromosome.}, isbn = {0014-4894}, author = {Bartholomeu, Daniella C. and Silva, Rosiane A. and Galv{\~a}o, Lucia M. C. and Najib M. El-Sayed and Donelson, John E. and Teixeira, Santuza M. R.} } @article {49632, title = {Trypanosoma cruzi: RNA structure and post-transcriptional control of tubulin gene expression.}, journal = {Exp Parasitol}, volume = {102}, year = {2002}, month = {2002 Nov-Dec}, pages = {123-33}, abstract = {

Changes in tubulin expression are among the biochemical and morphological adaptations that occur during the life cycle of Trypanosomatids. To investigate the mechanism responsible for the differential accumulation of tubulin mRNAs in Trypanosoma cruzi, we determine the sequences of alpha- and beta-tubulin transcripts and analyzed their expression during the life cycle of the parasite. Two beta-tubulin mRNAs of 1.9 and 2.3 kb were found to differ mainly by an additional 369 nucleotides at the end of the 3{\textquoteright} untranslated region (UTR). Although their transcription rates are similar in epimastigotes and amastigotes, alpha- and beta-tubulin transcripts are 3- to 6-fold more abundant in epimastigotes than in trypomastigotes and amastigotes. Accordingly, the half-lives of alpha- and beta-tubulin mRNAs are significantly higher in epimastigotes than in amastigotes. Transient transfection experiments indicated that positive regulatory elements occur in the 3{\textquoteright} UTR plus downstream intergenic region of the alpha-tubulin gene and that both positive and negative elements occur in the equivalent regions of the beta-tubulin gene.

}, keywords = {Animals, Base Sequence, Blotting, Northern, DNA, Complementary, DNA, Protozoan, Gene Expression Regulation, Half-Life, Life Cycle Stages, Molecular Sequence Data, RNA Processing, Post-Transcriptional, RNA, Messenger, RNA, Protozoan, Transcription, Genetic, Transfection, Trypanosoma cruzi, Tubulin}, issn = {0014-4894}, author = {Bartholomeu, Daniella C and Silva, Rosiane A and Galv{\~a}o, Lucia M C and el-Sayed, Najib M A and Donelson, John E and Teixeira, Santuza M R} } @article {38543, title = {Transforming cabbage into turnip: polynomial algorithm for sorting signed permutations by reversals}, journal = {J. ACMJ. ACM}, volume = {46}, year = {1999}, type = {10.1145/300515.300516}, abstract = {Genomes frequently evolve by reversals \&rgr;(i,j) that transform a gene order \&pgr;1 {\textellipsis} \&pgr;i\&pgr;i+1 {\textellipsis} \&pgr;j-1\&pgr;j {\textellipsis} \&pgr;n into \&pgr;1 {\textellipsis} \&pgr;i\&pgr;j-1 {\textellipsis} \&pgr;i+1\&pgr;j {\textellipsis} \&pgr;n. Reversal distance between permutations \&pgr; and \&sgr;is the minimum number of reversals to transform \&pgr; into \&Agr;. Analysis of genome rearrangements in molecular biology started in the late 1930{\textquoteright}s, when Dobzhansky and Sturtevant published a milestone paper presenting a rearrangement scenario with 17 inversions between the species of Drosophilia. Analysis of genomes evolving by inversions leads to a combinatorial problem of sorting by reversals studied in detail recently. We study sorting of signed permutations by reversals, a problem that adequately models rearrangements in a small genomes like chloroplast or mitochondrial DNA. The previously suggested approximation algorithms for sorting signed permutations by reversals compute the reversal distance between permutations with an astonishing accuracy for both simulated and biological data. We prove a duality theorem explaining this intriguing performance and show that there exists a {\textquotedblleft}hidden{\textquotedblright} parameter that allows one to compute the reversal distance between signed permutations in polynomial time.}, keywords = {Computational Biology, Genetics}, isbn = {0004-5411}, author = {Sridhar Hannenhalli and Pevzner, Pavel A.} } @article {38548, title = {Trends in the early careers of life scientists - Preface and executive summary}, journal = {Mol Biol CellMol Biol Cell}, volume = {9}, year = {1998}, author = {Tilghman, S. and Astin, H. S. and Brinkley, W. and Chilton, M. D. and Michael P. Cummings and Ehrenberg, R. G. and Fox, M. F. and Glenn, K. and Green, P. J. and Hans, S. and Kelman, A. and LaPidus, J. and Levin, B. and McIntosh, J. R. and Riecken, H. and Stephen, P. E.} } @article {38527, title = {Testing simple polygons}, journal = {Computational GeometryComputational Geometry}, volume = {8}, year = {1997}, type = {10.1016/S0925-7721(96)00015-6}, abstract = {We consider the problem of verifying a simple polygon in the plane using {\textquotedblleft}test points{\textquotedblright}. A test point is a geometric probe that takes as input a point in Euclidean space, and returns {\textquotedblleft}+{\textquotedblright} if the point is inside the object being probed or {\textquotedblleft}-{\textquotedblright} if it is outside. A verification procedure takes as input a description of a target object, including its location and orientation, and it produces a set of test points that are used to verify whether a test object matches the description. We give a procedure for verifying an n-sided, non-degenerate, simple target polygon using 5n test points. This testing strategy works even if the test polygon has n + 1 vertices, and we show a lower bound of 3n + 1 test points for this case. We also give algorithms using O(n) test points for simple polygons that may be degenerate and for test polygons that may have up to n + 2 vertices. All of these algorithms work for polygons with holes. We also discuss extensions of our results to higher dimensions.}, keywords = {probing, Testing, Verifying}, isbn = {0925-7721}, author = {Arkin, Esther M. and Belleville, Patrice and Mitchell, Joseph S. B. and Mount, Dave and Romanik, Kathleen and Salzberg, Steven and Souvaine, Diane} } @proceedings {38532, title = {To cut{\textellipsis} or not to cut (applications of comparative physical maps in molecular evolution)}, year = {1996}, month = {1996}, publisher = {Society for Industrial and Applied Mathematics}, address = {Philadelphia, PA, USA}, isbn = {0-89871-366-8}, author = {Sridhar Hannenhalli and Pevzner, Pavel} } @inbook {38534, title = {Towards a computational theory of genome rearrangements}, booktitle = {Computer Science TodayComputer Science Today}, series = {Lecture Notes in Computer Science}, volume = {1000}, year = {1995}, publisher = {Springer Berlin / Heidelberg}, organization = {Springer Berlin / Heidelberg}, abstract = {Analysis of genome rearrangements in molecular biology started in the late 1930{\textquoteright}s, when Dobzhansky and Sturtevant published a milestone paper presenting a rearrangement scenario with 17 inversions for the species of Drosophila. However, until recently there were no computer science results allowing a biologist to analyze genome rearrangements. The paper describes combinatorial problems motivated by genome rearrangements, surveys recently developed algorithms for genomic sequence comparison and presents applications of these algorithms to analyze rearrangements in herpes viruses, plant organelles, and mammalian chromosomes.}, isbn = {978-3-540-60105-0}, author = {Sridhar Hannenhalli and Pevzner, Pavel}, editor = {van Leeuwen, Jan} } @proceedings {38542, title = {Transforming cabbage into turnip: polynomial algorithm for sorting signed permutations by reversals}, year = {1995}, month = {1995}, publisher = {ACM}, type = {10.1145/225058.225112}, address = {New York, NY, USA}, isbn = {0-89791-718-9}, author = {Sridhar Hannenhalli and Pevzner, Pavel} } @mastersthesis {38544, title = {Transforming men into mice (a computational theory of genome rearrangements)}, year = {1995}, school = {The Pennsylvania State University}, author = {Sridhar Hannenhalli} } @proceedings {38545, title = {Transforming men into mice (polynomial algorithm for genomic distance problem)}, year = {1995}, month = {1995}, publisher = {IEEE Computer Society}, type = {http://doi.ieeecomputersociety.org/10.1109/SFCS.1995.492588}, address = {Los Alamitos, CA, USA}, abstract = {Many people believe that transformations of humans into mice happen only in fairy tales. However, despite some differences in appearance and habits, men and mice are genetically very similar. In the pioneering paper, J.H. Nadeau and B.A. Taylor (1984) estimated that surprisingly few genomic rearrangements (178/spl plusmn/39) happened since the divergence of human and mouse 80 million years ago. However, their analysis is nonconstructive and no rearrangement scenario for human-mouse evolution has been suggested yet. The problem is complicated by the fact that rearrangements in multi chromosomal genomes include inversions, translocations, fusions and fissions of chromosomes, a rather complex set of operations. As a result, at first glance, a polynomial algorithm for the genomic distance problem with all these operations looks almost as improbable as the transformation of a (real) man into a (real) mouse. We prove a duality theorem which expresses the genomic distance in terms of easily computable parameters reflecting different combinatorial properties of sets of strings. This theorem leads to a polynomial time algorithm for computing most parsimonious rearrangement scenarios. Based on this result and the latest comparative physical mapping data we have constructed a scenario of human-mouse evolution with 131 reversals/translocaitons/fusions/fissions. A combination of the genome rearrangement algorithm with the recently proposed experimental technique called ZOO FISH suggests a new constructive approach to the 100 year old problem of reconstructing mammalian evolution.}, keywords = {biology computing, combinatorial properties, comparative physical mapping data, computable parameters, duality (mathematics), duality theorem, evolution (biological), Genetics, genome rearrangement algorithm, genomic distance problem, genomic rearrangements, human-mouse evolution, mammalian evolution, multi chromosomal genomes, parsimonious rearrangement scenarios, pattern matching, polynomial algorithm, polynomial time algorithm, set theory, sorting, string matching, strings, zoo fish}, author = {Sridhar Hannenhalli and Pevzner, P. A.} } @article {38546, title = {Transmission patterns of eukaryotic transposable elements - arguments for and against horizontal transfer}, journal = {Trends Ecol EvolTrends Ecol Evol}, volume = {9}, year = {1994}, abstract = {Recent studies have demonstrated that several classes of transposable elements are widely distributed within eukaryotes. Horizontal transmission of these transposable elements has often been invoked in order to explain the observed variation and relationships within and between species. These same patterns of variation and relationships, however, may originate from processes that do not involve the lateral transfer of genetic material across species.}, author = {Michael P. Cummings} } @article {49720, title = {Transcription of cloned tRNA and 5S RNA genes in a Drosophila cell free extract.}, journal = {Nucleic Acids Res}, volume = {9}, year = {1981}, month = {1981 Aug 25}, pages = {3907-18}, abstract = {

We describe the preparation of a cell-free extract from Drosophila Kc cells which allows transcription of a variety of cloned eukaryotic RNA polymerase III genes. The extract has low RNA-processing nuclease activity and thus the major products obtained are primary transcripts.

}, keywords = {Animals, Cell-Free System, Cloning, Molecular, Drosophila, In Vitro Techniques, RNA, RNA Polymerase III, RNA, Transfer, Transcription, Genetic, Xenopus laevis}, issn = {0305-1048}, author = {Dingermann, T and Sharp, S and Appel, B and DeFranco, D and Mount, S and Heiermann, R and Pongs, O and S{\"o}ll, D} }