@article {49749, title = {Measuring differential gene expression by short read sequencing: quantitative comparison to 2-channel gene expression microarrays.}, journal = {BMC Genomics}, volume = {10}, year = {2009}, month = {2009}, pages = {221}, abstract = {

BACKGROUND: High-throughput cDNA synthesis and sequencing of poly(A)-enriched RNA is rapidly emerging as a technology competing to replace microarrays as a quantitative platform for measuring gene expression.

RESULTS: Consequently, we compared full length cDNA sequencing to 2-channel gene expression microarrays in the context of measuring differential gene expression. Because of its comparable cost to a gene expression microarray, our study focused on the data obtainable from a single lane of an Illumina 1 G sequencer. We compared sequencing data to a highly replicated microarray experiment profiling two divergent strains of S. cerevisiae.

CONCLUSION: Using a large number of quantitative PCR (qPCR) assays, more than previous studies, we found that neither technology is decisively better at measuring differential gene expression. Further, we report sequencing results from a diploid hybrid of two strains of S. cerevisiae that indicate full length cDNA sequencing can discover heterozygosity and measure quantitative allele-specific expression simultaneously.

}, keywords = {algorithms, DNA, Complementary, DNA, Fungal, Gene Expression Profiling, Oligonucleotide Array Sequence Analysis, Saccharomyces cerevisiae, sequence alignment, Sequence Analysis, DNA}, issn = {1471-2164}, doi = {10.1186/1471-2164-10-221}, author = {Bloom, Joshua S and Khan, Zia and Kruglyak, Leonid and Singh, Mona and Caudy, Amy A} } @article {49682, title = {Comprehensive analysis of alternative splicing in rice and comparative analyses with Arabidopsis.}, journal = {BMC Genomics}, volume = {7}, year = {2006}, month = {2006}, pages = {327}, abstract = {

BACKGROUND: Recently, genomic sequencing efforts were finished for Oryza sativa (cultivated rice) and Arabidopsis thaliana (Arabidopsis). Additionally, these two plant species have extensive cDNA and expressed sequence tag (EST) libraries. We employed the Program to Assemble Spliced Alignments (PASA) to identify and analyze alternatively spliced isoforms in both species.

RESULTS: A comprehensive analysis of alternative splicing was performed in rice that started with >1.1 million publicly available spliced ESTs and over 30,000 full length cDNAs in conjunction with the newly enhanced PASA software. A parallel analysis was performed with Arabidopsis to compare and ascertain potential differences between monocots and dicots. Alternative splicing is a widespread phenomenon (observed in greater than 30\% of the loci with transcript support) and we have described nine alternative splicing variations. While alternative splicing has the potential to create many RNA isoforms from a single locus, the majority of loci generate only two or three isoforms and transcript support indicates that these isoforms are generally not rare events. For the alternate donor (AD) and acceptor (AA) classes, the distance between the splice sites for the majority of events was found to be less than 50 basepairs (bp). In both species, the most frequent distance between AA is 3 bp, consistent with reports in mammalian systems. Conversely, the most frequent distance between AD is 4 bp in both plant species, as previously observed in mouse. Most alternative splicing variations are localized to the protein coding sequence and are predicted to significantly alter the coding sequence.

CONCLUSION: Alternative splicing is widespread in both rice and Arabidopsis and these species share many common features. Interestingly, alternative splicing may play a role beyond creating novel combinations of transcripts that expand the proteome. Many isoforms will presumably have negative consequences for protein structure and function, suggesting that their biological role involves post-transcriptional regulation of gene expression.

}, keywords = {Alternative Splicing, Arabidopsis, DNA, Complementary, Expressed Sequence Tags, Oryza}, issn = {1471-2164}, doi = {10.1186/1471-2164-7-327}, author = {Campbell, Matthew A and Haas, Brian J and Hamilton, John P and Mount, Stephen M and Buell, C Robin} } @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 {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} }