@article {49734, title = {Genomic variation. Impact of regulatory variation from RNA to protein.}, journal = {Science}, volume = {347}, year = {2015}, month = {2015 Feb 6}, pages = {664-7}, abstract = {

The phenotypic consequences of expression quantitative trait loci (eQTLs) are presumably due to their effects on protein expression levels. Yet the impact of genetic variation, including eQTLs, on protein levels remains poorly understood. To address this, we mapped genetic variants that are associated with eQTLs, ribosome occupancy (rQTLs), or protein abundance (pQTLs). We found that most QTLs are associated with transcript expression levels, with consequent effects on ribosome and protein levels. However, eQTLs tend to have significantly reduced effect sizes on protein levels, which suggests that their potential impact on downstream phenotypes is often attenuated or buffered. Additionally, we identified a class of cis QTLs that affect protein abundance with little or no effect on messenger RNA or ribosome levels, which suggests that they may arise from differences in posttranslational regulation.

}, keywords = {3{\textquoteright} Flanking Region, 5{\textquoteright} Flanking Region, Cell Line, Exons, Gene Expression Regulation, Genetic Variation, HUMANS, PHENOTYPE, Protein Biosynthesis, Quantitative Trait Loci, Ribosomes, RNA, Messenger, Transcription, Genetic}, issn = {1095-9203}, doi = {10.1126/science.1260793}, author = {Battle, Alexis and Khan, Zia and Wang, Sidney H and Mitrano, Amy and Ford, Michael J and Pritchard, Jonathan K and Gilad, Yoav} } @article {49738, title = {Primate transcript and protein expression levels evolve under compensatory selection pressures.}, journal = {Science}, volume = {342}, year = {2013}, month = {2013 Nov 29}, pages = {1100-4}, abstract = {

Changes in gene regulation have likely played an important role in the evolution of primates. Differences in messenger RNA (mRNA) expression levels across primates have often been documented; however, it is not yet known to what extent measurements of divergence in mRNA levels reflect divergence in protein expression levels, which are probably more important in determining phenotypic differences. We used high-resolution, quantitative mass spectrometry to collect protein expression measurements from human, chimpanzee, and rhesus macaque lymphoblastoid cell lines and compared them to transcript expression data from the same samples. We found dozens of genes with significant expression differences between species at the mRNA level yet little or no difference in protein expression. Overall, our data suggest that protein expression levels evolve under stronger evolutionary constraint than mRNA levels.

}, keywords = {Animals, Evolution, Molecular, Gene Expression Regulation, HUMANS, Macaca mulatta, Pan troglodytes, Protein Biosynthesis, RNA, Messenger, Selection, Genetic, Species Specificity, Transcription, Genetic}, issn = {1095-9203}, doi = {10.1126/science.1242379}, author = {Khan, Zia and Ford, Michael J and Cusanovich, Darren A and Mitrano, Amy and Pritchard, Jonathan K and Gilad, Yoav} } @article {49652, title = {The genome and its implications.}, journal = {Adv Parasitol}, volume = {75}, year = {2011}, month = {2011}, pages = {209-30}, abstract = {

Trypanosoma cruzi has a heterogeneous population composed of a pool of strains that circulate in the domestic and sylvatic cycles. Genome sequencing of the clone CL Brener revealed a highly repetitive genome of about 110Mb containing an estimated 22,570 genes. Because of its hybrid nature, sequences representing the two haplotypes have been generated. In addition, a repeat content close to 50\% made the assembly of the estimated 41 pairs of chromosomes quite challenging. Similar to other trypanosomatids, the organization of T. cruzi chromosomes was found to be very peculiar, with protein-coding genes organized in long polycistronic transcription units encoding 20 or more proteins in one strand separated by strand switch regions. Another remarkable feature of the T. cruzi genome is the massive expansion of surface protein gene families. Because of the high genetic diversity of the T. cruzi population, sequencing of additional strains and comparative genomic and transcriptome analyses are in progress. Five years after its publication, the genome data have proven to be an essential tool for the study of T. cruzi and increasing efforts to translate this knowledge into the development of new modes of intervention to control Chagas disease are underway.

}, keywords = {Animals, Antigens, Protozoan, Chagas Disease, Chromosomes, Comparative Genomic Hybridization, DNA, Protozoan, Gene Expression Regulation, Genetic Variation, Genome, Protozoan, Host-Parasite Interactions, HUMANS, Species Specificity, Synteny, Transcription, Genetic, Transfection, Trypanosoma cruzi}, issn = {0065-308X}, doi = {10.1016/B978-0-12-385863-4.00010-1}, author = {Teixeira, Santuza M and El-Sayed, Najib M and Ara{\'u}jo, Patr{\'\i}cia R} } @article {38347, title = {Influence of host gene transcription level and orientation on HIV-1 latency in a primary-cell model}, journal = {Journal of virologyJournal of virology}, volume = {85}, year = {2011}, note = {http://www.ncbi.nlm.nih.gov/pubmed/21430059?dopt=Abstract}, type = {10.1128/JVI.02536-10}, abstract = {Human immunodeficiency virus type 1 (HIV-1) establishes a latent reservoir in resting memory CD4(+) T cells. This latent reservoir is a major barrier to the eradication of HIV-1 in infected individuals and is not affected by highly active antiretroviral therapy (HAART). Reactivation of latent HIV-1 is a possible strategy for elimination of this reservoir. The mechanisms with which latency is maintained are unclear. In the analysis of the regulation of HIV-1 gene expression, it is important to consider the nature of HIV-1 integration sites. In this study, we analyzed the integration and transcription of latent HIV-1 in a primary CD4(+) T cell model of latency. The majority of integration sites in latently infected cells were in introns of transcription units. Serial analysis of gene expression (SAGE) demonstrated that more than 90\% of those host genes harboring a latent integrated provirus were transcriptionally active, mostly at high levels. For latently infected cells, we observed a modest preference for integration in the same transcriptional orientation as the host gene (63.8\% versus 36.2\%). In contrast, this orientation preference was not observed in acutely infected or persistently infected cells. These results suggest that transcriptional interference may be one of the important factors in the establishment and maintenance of HIV-1 latency. Our findings suggest that disrupting the negative control of HIV-1 transcription by upstream host promoters could facilitate the reactivation of latent HIV-1 in some resting CD4(+) T cells.}, keywords = {CD4-Positive T-Lymphocytes, Cells, Cultured, Gene Expression Profiling, Gene Expression Regulation, Viral, HIV-1, HUMANS, Transcription, Genetic, Virus Integration, Virus Latency}, author = {Shan, Liang and Yang, Hung-Chih and Rabi, S. Alireza and H{\'e}ctor Corrada Bravo and Shroff, Neeta S. and Irizarry, Rafael A. and Zhang, Hao and Margolick, Joseph B. and Siliciano, Janet D. and Siliciano, Robert F.} } @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 {49685, title = {Improving the Arabidopsis genome annotation using maximal transcript alignment assemblies.}, journal = {Nucleic Acids Res}, volume = {31}, year = {2003}, month = {2003 Oct 1}, pages = {5654-66}, abstract = {

The spliced alignment of expressed sequence data to genomic sequence has proven a key tool in the comprehensive annotation of genes in eukaryotic genomes. A novel algorithm was developed to assemble clusters of overlapping transcript alignments (ESTs and full-length cDNAs) into maximal alignment assemblies, thereby comprehensively incorporating all available transcript data and capturing subtle splicing variations. Complete and partial gene structures identified by this method were used to improve The Institute for Genomic Research Arabidopsis genome annotation (TIGR release v.4.0). The alignment assemblies permitted the automated modeling of several novel genes and >1000 alternative splicing variations as well as updates (including UTR annotations) to nearly half of the approximately 27 000 annotated protein coding genes. The algorithm of the Program to Assemble Spliced Alignments (PASA) tool is described, as well as the results of automated updates to Arabidopsis gene annotations.

}, keywords = {algorithms, Alternative Splicing, Arabidopsis, DNA, Complementary, Expressed Sequence Tags, Genome, Plant, Introns, Plant Proteins, RNA, Plant, sequence alignment, software, Transcription, Genetic, Untranslated Regions}, issn = {1362-4962}, author = {Haas, Brian J and Delcher, Arthur L and Mount, Stephen M and Wortman, Jennifer R and Smith, Roger K and Hannick, Linda I and Maiti, Rama and Ronning, Catherine M and Rusch, Douglas B and Town, Christopher D and Salzberg, Steven L and White, Owen} } @article {49629, title = {Analysis of stage-specific gene expression in the bloodstream and the procyclic form of Trypanosoma brucei using a genomic DNA-microarray.}, journal = {Mol Biochem Parasitol}, volume = {123}, year = {2002}, month = {2002 Aug 28}, pages = {115-23}, abstract = {

A microarray comprising 21,024 different PCR products spotted on glass slides was constructed for gene expression studies on Trypanosoma brucei. The arrayed fragments were generated from a T. brucei shotgun clone library, which had been prepared from randomly sheared and size-fractionated genomic DNA. For the identification of stage-specific gene activity, total RNA from in vitro cultures of the human, long slender form and the insect, procyclic form of the parasite was labelled and hybridised to the microarray. Approximately 75\% of the genomic fragments produced a signal and about 2\% exhibited significant differences between the transcript levels in the bloodstream and procyclic forms. A few results were confirmed by Northern blot analysis or reverse-transcription and PCR. Three hundred differentially regulated clones have been selected for sequencing. So far, of 33 clones that showed about 2-fold or more over-expression in bloodstream forms, 15 contained sequences similar to those of VSG expression sites and at least six others appeared non-protein-coding. Of 29 procyclic-specific clones, at least eight appeared not to be protein-coding. A surprisingly large proportion of known regulated genes was already identified in this small sample, and some new ones were found, illustrating the utility of genomic arrays.

}, keywords = {Animals, Blotting, Northern, Escherichia coli, Gene expression, Gene Expression Profiling, Genes, Protozoan, HUMANS, Life Cycle Stages, Molecular Sequence Data, Oligonucleotide Array Sequence Analysis, Polymerase Chain Reaction, Transcription, Genetic, Trypanosoma brucei brucei}, issn = {0166-6851}, author = {Diehl, Susanne and Diehl, Frank and El-Sayed, Najib M and Clayton, Christine and Hoheisel, J{\"o}rg D} } @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 {49692, title = {The genome sequence of Drosophila melanogaster.}, journal = {Science}, volume = {287}, year = {2000}, month = {2000 Mar 24}, pages = {2185-95}, abstract = {

The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the approximately 120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes approximately 13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.

}, keywords = {Animals, Biological Transport, Chromatin, Cloning, Molecular, Computational Biology, Contig Mapping, Cytochrome P-450 Enzyme System, DNA Repair, DNA Replication, Drosophila melanogaster, Euchromatin, Gene Library, Genes, Insect, Genome, Heterochromatin, Insect Proteins, Nuclear Proteins, Protein Biosynthesis, Sequence Analysis, DNA, Transcription, Genetic}, issn = {0036-8075}, author = {Adams, M D and Celniker, S E and Holt, R A and Evans, C A and Gocayne, J D and Amanatides, P G and Scherer, S E and Li, P W and Hoskins, R A and Galle, R F and George, R A and Lewis, S E and Richards, S and Ashburner, M and Henderson, S N and Sutton, G G and Wortman, J R and Yandell, M D and Zhang, Q and Chen, L X and Brandon, R C and Rogers, Y H and Blazej, R G and Champe, M and Pfeiffer, B D and Wan, K H and Doyle, C and Baxter, E G and Helt, G and Nelson, C R and Gabor, G L and Abril, J F and Agbayani, A and An, H J and Andrews-Pfannkoch, C and Baldwin, D and Ballew, R M and Basu, A and Baxendale, J and Bayraktaroglu, L and Beasley, E M and Beeson, K Y and Benos, P V and Berman, B P and Bhandari, D and Bolshakov, S and Borkova, D and Botchan, M R and Bouck, J and Brokstein, P and Brottier, P and Burtis, K C and Busam, D A and Butler, H and Cadieu, E and Center, A and Chandra, I and Cherry, J M and Cawley, S and Dahlke, C and Davenport, L B and Davies, P and de Pablos, B and Delcher, A and Deng, Z and Mays, A D and Dew, I and Dietz, S M and Dodson, K and Doup, L E and Downes, M and Dugan-Rocha, S and Dunkov, B C and Dunn, P and Durbin, K J and Evangelista, C C and Ferraz, C and Ferriera, S and Fleischmann, W and Fosler, C and Gabrielian, A E and Garg, N S and Gelbart, W M and Glasser, K and Glodek, A and Gong, F and Gorrell, J H and Gu, Z and Guan, P and Harris, M and Harris, N L and Harvey, D and Heiman, T J and Hernandez, J R and Houck, J and Hostin, D and Houston, K A and Howland, T J and Wei, M H and Ibegwam, C and Jalali, M and Kalush, F and Karpen, G H and Ke, Z and Kennison, J A and Ketchum, K A and Kimmel, B E and Kodira, C D and Kraft, C and Kravitz, S and Kulp, D and Lai, Z and Lasko, P and Lei, Y and Levitsky, A A and Li, J and Li, Z and Liang, Y and Lin, X and Liu, X and Mattei, B and McIntosh, T C and McLeod, M P and McPherson, D and Merkulov, G and Milshina, N V and Mobarry, C and Morris, J and Moshrefi, A and Mount, S M and Moy, M and Murphy, B and Murphy, L and Muzny, D M and Nelson, D L and Nelson, D R and Nelson, K A and Nixon, K and Nusskern, D R and Pacleb, J M and Palazzolo, M and Pittman, G S and Pan, S and Pollard, J and Puri, V and Reese, M G and Reinert, K and Remington, K and Saunders, R D and Scheeler, F and Shen, H and Shue, B C and Sid{\'e}n-Kiamos, I and Simpson, M and Skupski, M P and Smith, T and Spier, E and Spradling, A C and Stapleton, M and Strong, R and Sun, E and Svirskas, R and Tector, C and Turner, R and Venter, E and Wang, A H and Wang, X and Wang, Z Y and Wassarman, D A and Weinstock, G M and Weissenbach, J and Williams, S M and Worley, K C and Wu, D and Yang, S and Yao, Q A and Ye, J and Yeh, R F and Zaveri, J S and Zhan, M and Zhang, G and Zhao, Q and Zheng, L and Zheng, X H and Zhong, F N and Zhong, W and Zhou, X and Zhu, S and Zhu, X and Smith, H O and Gibbs, R A and Myers, E W and Rubin, G M and Venter, J C} } @article {49705, title = {Characterization of enhancer-of-white-apricot in Drosophila melanogaster.}, journal = {Genetics}, volume = {126}, year = {1990}, month = {1990 Dec}, pages = {1061-9}, abstract = {

The white-apricot (wa) allele differs from the wild-type white gene by the presence of the retrovirus-like transposable element copia within the transcription unit. Most RNAs derived from wa have 3{\textquoteright} termini within this insertion, and only small amounts of structurally normal RNA are produced. The activity of wa is reduced in trans by a semidominant mutation in the gene Enhancer-of-white-apricot (E(wa). Flies that are wa and heterozygous for the enhancer have eyes which are much lighter than the orange-yellow of wa alone while E(wa) homozygotes have white eyes. This semidominant effect on pigmentation is correlated with a corresponding decrease in white RNA having wild type structure, and flies homozygous for E(wa) have increased levels of aberrant RNAs. Three reverant alleles of E(wa) generated by reversion of the dominant enhancer phenotype with gamma radiation are noncomplementing recessive lethals, with death occurring during the larval stage. The effects on wa eye pigmentation of varying doses of the original E(wa) allele, the wild type allele, and the revertant alleles suggest that the original E(wa) allele produces a product that interferes with the activity of the wild type gene and that the revertants are null alleles. We propose that the E(wa) gene product influences the activity of the downstream copia long terminal repeat in 3{\textquoteright} end formation.

}, keywords = {Alleles, Animals, Blotting, Northern, DNA Transposable Elements, Drosophila melanogaster, Eye Color, Female, Heterozygote, Homozygote, Male, Nucleic Acid Hybridization, PHENOTYPE, Poly A, Reproduction, RNA, RNA, Messenger, Transcription, Genetic}, issn = {0016-6731}, author = {Peng, X B and Mount, S M} } @article {49713, title = {Lessons from mutant globins.}, journal = {Nature}, volume = {303}, year = {1983}, month = {1983 Jun 2-8}, pages = {380-1}, keywords = {Globins, HUMANS, Mutation, RNA, Messenger, Thalassemia, Transcription, Genetic}, issn = {0028-0836}, author = {Mount, S and Steitz, J} } @article {49715, title = {Pseudogenes for human small nuclear RNA U3 appear to arise by integration of self-primed reverse transcripts of the RNA into new chromosomal sites.}, journal = {Cell}, volume = {32}, year = {1983}, month = {1983 Feb}, pages = {461-72}, abstract = {

We find that both human and rat U3 snRNA can function as self-priming templates for AMV reverse transcriptase in vitro. The 74 base cDNA is primed by the 3{\textquoteright} end of intact U3 snRNA, and spans the characteristically truncated 69 or 70 base U3 sequence found in four different human U3 pseudogenes. The ability of human and rat U3 snRNA to self-prime is consistent with a U3 secondary structure model derived by a comparison between rat U3 snRNA and the homologous D2 snRNA from Dictyostelium discoideum. We propose that U3 pseudogenes are generated in vivo by integration of a self-primed cDNA copy of U3 snRNA at new chromosomal sites. We also consider the possibility that the same cDNA mediates gene conversion at the 5{\textquoteright} end of bona fide U3 genes where, over the entire region spanned by the U3 cDNA, the two rat U3 sequence variants U3A and U3B are identical.

}, keywords = {Animals, Base Sequence, DNA, genes, HUMANS, Nucleic Acid Conformation, Rats, Recombination, Genetic, Repetitive Sequences, Nucleic Acid, RNA, RNA, Small Nuclear, RNA-Directed DNA Polymerase, Templates, Genetic, Transcription, Genetic}, issn = {0092-8674}, author = {Bernstein, L B and Mount, S M and Weiner, A M} } @article {49716, title = {Small ribonucleoproteins from eukaryotes: structures and roles in RNA biogenesis.}, journal = {Cold Spring Harb Symp Quant Biol}, volume = {47 Pt 2}, year = {1983}, month = {1983}, pages = {893-900}, keywords = {Animals, Base Sequence, HeLa Cells, HUMANS, Mice, Molecular Weight, Nucleic Acid Conformation, Nucleic Acid Hybridization, Nucleoproteins, Ribonucleoproteins, Ribonucleoproteins, Small Nuclear, RNA Polymerase III, Transcription, Genetic}, issn = {0091-7451}, author = {Steitz, J A and Wolin, S L and Rinke, J and Pettersson, I and Mount, S M and Lerner, E A and Hinterberger, M and Gottlieb, E} } @article {49711, title = {Splicing of messenger RNA precursors is inhibited by antisera to small nuclear ribonucleoprotein.}, journal = {Cell}, volume = {35}, year = {1983}, month = {1983 Nov}, pages = {101-7}, abstract = {

A mouse monoclonal antibody and human autoimmune sera directed against various classes of small ribonucleoprotein particles have been tested for inhibition of mRNA splicing in a soluble in vitro system. The splicing of the first and second leader exons of adenovirus late RNA was inhibited only by those sera that reacted with U1 RNP. Both U1 RNP-specific human autoimmune serum and sera directed against the Sm class of small nuclear RNPs, including a mouse monoclonal antibody, specifically inhibited splicing. Antisera specific for U2 RNP had no effect on splicing nor did antisera specific for the La or Ro class of small RNPs. These results suggest that U1 RNP is essential for the splicing of mRNA precursors.

}, keywords = {Adenoviruses, Human, Antigens, Autoantigens, Base Sequence, Cell Extracts, HeLa Cells, HUMANS, Immune Sera, Nucleic Acid Precursors, Ribonucleoproteins, Ribonucleoproteins, Small Nuclear, RNA, RNA Precursors, RNA Splicing, RNA, Messenger, RNA, Small Cytoplasmic, RNA, Viral, Transcription, Genetic}, issn = {0092-8674}, author = {Padgett, R A and Mount, S M and Steitz, J A and Sharp, P A} } @article {49718, title = {Structure and function of small ribonucleoproteins from eukaryotic cells.}, journal = {Princess Takamatsu Symp}, volume = {12}, year = {1982}, month = {1982}, pages = {101-7}, abstract = {

Autoantibodies from patients with systemic lupus erythematosus and other related diseases have been used to identify and study small RNA-protein complexes from mammalian cells. Properties of three previously described and several new classes of small ribonucleoproteins (RNPs) are reviewed. The sequence of Drosophila U1 RNA reveals that the region proposed to pair with 5{\textquoteright} splice junctions is conserved, while that proposed to interact with 3{\textquoteright} junctions diverges; this forces some revision of the model for U1 small nuclear (sn)RNP participation in hnRNA splicing. Further characterization of the Ro and La small RNPs has shown that the Ro small cytoplasmic (sc)RNPs are a subclass of La RNPs. Both tRNA and 5S rRNA precursors are at least transiently associated with the La protein. This raises the possibility that the La protein may be an RNA polymerase III transcription factor.

}, keywords = {Antigen-Antibody Complex, Autoantibodies, HUMANS, Lupus Erythematosus, Systemic, Nucleoproteins, Ribonucleoproteins, RNA Polymerase III, Transcription, Genetic}, author = {Steitz, J A and Berg, C and Gottlieb, E and Hardin, J A and Hashimoto, C and Hendrick, J P and Hinterberger, M and Krikeles, M and Lerner, M R and Mount, S M} } @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} }