Poster abstracts

Poster number 31 submitted by Jie Chen

Alternative Polyadenylation and miRNA targets in Arabidopsis

Jie Chen (Botany Department, Miami University, Oxford), Xiaohui Wu (Botany Department, Miami University, Oxford), Q. Quinn Li (Botany Department, Miami University, Oxford)

Abstract:
Based on a large-scale dataset we generated and analyzed, 18 Arabidopsis genes have been identified to have at least one Alternative PolyAdenylation (APA) site at either end of a potential miRNA target in the pre-mRNA and thus generating two transcript isoforms. The use of the APA site (closer to 5’UTR) in the pre-mRNA would eliminate the miRNA target and thus escape miRNA based regulations, while the use of the other APA site (away from 5’UTR) would retain the miRNA target and thus would subject to regulation. We hypothesize that the selection of an APA site itself is a critical regulatory event through which the expression of the gene is modulated by respective miRNA. Another interlinked hypothesis is that miRNA also affect the selection of APA sites by interacting with cleavage and polyadenylation process. Four genes out of the 18 were selected. APA sites and the targets of the miRNA are first confirmed by reverse transcription PCR and over-expression approaches. Then, respective conditions that may lead to differential use of the APA sites of each of the four genes, including developmental and environmental responses, will be used to test if the impact of the APA and miRNA in these responses. Adjacent APA sites of two of those candidate genes have been confirmed. Further results will be presented.

References:
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Mayr, C., and Bartel, D.P. (2009). Widespread Shortening of 3 \' UTRs by Alternative Cleavage and Polyadenylation Activates Oncogenes in Cancer Cells. Cell 138, 673-684.
Rubio-Somoza, I., Cuperus, J., Weigel, D. , Carrington J. C. (2009). Regulation and functional specialization of small RNA–target nodes during plant development. Plant Biology 2009, 12:622–627.
Shen, Y. Genome wide studies of mRNA 3’-end processing signals and alternative polyadenylation in plants, Ph.D. Dissertation, Miami University, Oxford, USA. 2009.

Keywords: messenger RNA, Alternative Polyadenylation, micro RNA