Project description:Use 3ʹ region extraction and deep sequencing (3'READS) and bioinformatics techniques to profile alternative polyadenylation and gene regulation in plant Arabidopsis thaliana exposed to light and darkness
Project description:Alternative polyadenylation has been implicated as an important regulator of gene expression. In some cases, alternative polyadenylation is known to couple with alternative splicing to influence last intron removal. However, it is unknown whether alternative polyadenylation events influence alternative splicing decisions at upstream exons. Knockdown of the polyadenylation factors CFIm25 or CstF64 was used as an approach in identifying alternative polyadenylation and alternative splicing events on a genome-wide scale. Although hundreds of alternative splicing events were found to be differentially spliced in the knockdown of CstF64, genes associated with alternative polyadenylation did not exhibit an increased incidence of alternative splicing. These results demonstrate that the coupling between alternative polyadenylation and alternative splicing is usually limited to defining the last exon. The striking influence of CstF64 knockdown on alternative splicing can be explained through its effects on UTR selection of known splicing regulators such as hnRNP A2/B1, thereby indirectly influencing splice site selection. We conclude that changes in the expression of the polyadenylation factor CstF64 influences alternative splicing through indirect effects. HeLa cell line was stably transfected with shRNA plasmids targeting CstF64. Total RNA was isolated from CstF64 KD cells and wild-type control cells using Trizol according to manufacturerâs protocols. Samples were deep sequenced in duplicate using the Illumina GAIIx system.
Project description:Alternative polyadenylation (APA) is an important post-transcriptional modification implicated in development. Female germline stem cell (FGSC) is unipotent and capable of giving rise to oocyte. However, whether alternative polyadenylation plays a role in self-renew and cell fate determination of FGSCs remain elusive. Here, we used 3T-Seq developed in our lab to profile genome-wide 3a termini of transcripts and delineate APA sites in mouse FGSCs and explored the biological significance of APA modulation in FGSC identity.