tailieunhanh - Báo cáo y học: "Identification of novel exons and transcribed regions by chimpanzee transcriptome sequencing"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: Identification of novel exons and transcribed regions by chimpanzee transcriptome sequencing. | Wetterbom et al. Genome Biology 2010 11 R78 http 2010 11 7 R78 w Genome Biology RESEARCH _ Open Access Identification of novel exons and transcribed regions by chimpanzee transeriptome sequencing Anna Wetterbom Adam Ameur Lars Feuk Ulf Gyllensten and Lucia Cavelier Abstract Background We profile the chimpanzee transcriptome by using deep sequencing of cDNA from brain and liver aiming to quantify expression of known genes and to identify novel transcribed regions. Results Using stringent criteria for transcription we identify 12 843 expressed genes with a majority being found in both tissues. We further identify 9 826 novel transcribed regions that are not overlapping with annotated exons mRNAs or ESTs. Over 80 of the novel transcribed regions map within or in the vicinity of known genes and by combining sequencing data with de novo splice predictions we predict several of the novel transcribed regions to be new exons or 3 UTRs. For approximately 350 novel transcribed regions the corresponding DNA sequence is absent in the human reference genome. The presence of novel transcribed regions in five genes and in one intergenic region is further validated with RT-PCR. Finally we describe and experimentally validate a putative novel multi-exon gene that belongs to the ATP-cassette transporter gene family. This gene does not appear to be functional in human since one exon is absent from the human genome. In addition to novel exons and UTRs novel transcribed regions may also stem from different types of noncoding transcripts. We note that expressed repeats and introns from unspliced mRNAs are especially common in our data. Conclusions Our results extend the chimpanzee gene catalogue with a large number of novel exons and 3 UTRs and thus support the view that mammalian gene annotations are not yet complete. Background It is generally believed that comparisons at the genome and transcriptome levels are powerful strategies towards understanding the molecular