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Báo cáo y học: "Detection and analysis of alternative splicing in Yarrowia lipolytica reveal structural constraints facilitating nonsense-mediated decay of intron-retaining transcripts"

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: Detection and analysis of alternative splicing in Yarrowia lipolytica reveal structural constraints facilitating nonsense-mediated decay of intron-retaining transcripts. | Mekouar et al. Genome Biology 2010 11 R65 http genomebiology.eom 2010 11 6 R65 w Genome Biology RESEARCH Open Access Detection and analysis of alternative splicing in Yarrowia lipolytica reveal structural constraints facilitating nonsense-mediated decay of intron-retaining transcripts Meryem Mekouar 1 Isabelle Blanc-Lenfle1 Christophe Ozanne1 Corinne Da Silva2 Corinne Cruaud2 Patrick Wincker2 Claude Gaillardin1 and Cécile Neuvéglise 1 Abstract Background Hemiascomycetous yeasts have intron-poor genomes with very few cases of alternative splicing. Most of the reported examples result from intron retention in Saccharomyces cerevisiae and some have been shown to be functionally significant. Here we used transcriptome-wide approaches to evaluate the mechanisms underlying the generation of alternative transcripts in Yarrowialipolytica a yeast highly divergent from S. cerevisiae. Results Experimental investigation of Y lipolytica gene models identified several cases of alternative splicing mostly generated by intron retention principally affecting the first intron of the gene. The retention of introns almost invariably creates a premature termination codon as a direct consequence of the structure of intron boundaries. An analysis of Y lipolytica introns revealed that introns of multiples of three nucleotides in length particularly those without stop codons were underrepresented. In other organisms premature termination codon-containing transcripts are targeted for degradation by the nonsense-mediated mRNA decay NMD machinery. In Y. lipolytica homologs of S. cerevisiae UPF1 and UPF2 genes were identified but not UPF3. The inactivation of Y lipolytica UPF1 and UPF2 resulted in the accumulation of unspliced transcripts of a test set of genes. Conclusions Y lipolytica is the hemiascomycete with the most intron-rich genome sequenced to date and it has several unusual genes with large introns or alternative transcription start sites or introns in the 5 UTR. Our results suggest