2 Arctic Region Supercomputing Center

Alternative initiation, splicing, and polyadenylation are key mechanisms used by many organisms to generate diversity among mature mRNA transcripts originating from the same transcription unit. While previous computational analyses of alternative polyadenylation have focused on polyadenylation activ...

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Bibliographic Details
Main Authors: Jun Yan, Thomas G. Marr
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
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Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.556.3229
http://physics.nyu.edu/~jy272/altA/altA.pdf
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Summary:Alternative initiation, splicing, and polyadenylation are key mechanisms used by many organisms to generate diversity among mature mRNA transcripts originating from the same transcription unit. While previous computational analyses of alternative polyadenylation have focused on polyadenylation activities within or downstream of the normal 3 ' terminal exons, we present the results of the first genome-wide analysis of patterns of alternative polyadenylation in the human, mouse, and rat genomes occurring over the entire transcribed regions of mRNAs using 3 ' ESTs with polyA tails aligned to genomic sequences. Four distinct classes of patterns of alternative polyadenylation result from this analysis: tandem polyA sites, composite exons, hidden exons, and truncated exons. We estimate that at least 49% (human), 31 % (mouse), and 28 % (rat) of polyadenylated transcription units have alternative polyadenylation. A portion of these alternative polyadenylation events result in new protein isoforms.