Poster abstracts

Poster number 91 submitted by Denghui Xing

Polyadenylation Factor PCFS4 Physically Interacts With the Loci of a Subset of Genes Involved in Arabidopsis Development

Denghui Xing (Botany, Miami Univeristy), Quinn Li (Botany, Miami University)

Abstract:
Arabidopsis polyadenylation factor, PCFS4, an ortholog of human and yeast PCF11, functions in Arabidopsis flowering time control, leaf development and phyllotaxy determination. The role of PCFS4 in flowering time control is partially mediated by FLC and correlated with the regulation of alternative polyadenylation (APA) of FCA. PCFS4 forms an in vivo complex with FY, another polyadenylation factor and a regulator of the APA of FCA, suggesting its involvement with a polyadenylation machinery that acts on the APA of FCA. The roles of PCFS4 in leaf development and phyllotaxy, however, could not be explained by the APA of FCA. We thus speculated that there must be additional genes, other than FCA, being targeted by PCFS4. To identify these targets, we compared the transcriptomes of pcfs4-1 mutant and wild type using tiling microarray assays. 68 Differentially Processed Genes (putative direct targets) in the mutant were identified and largely confirmed by RT-qPCR. To further explore if PCFS4 directly targets on the loci of those genes, we performed a ChIP assay for one of the targets, ATIM, using PCFS4-TAP recombinant protein. We found PCFS4-TAP was indeed enriched on the 3’ end of ATIM locus. A further Illumina-Seq assay following the ChIP precipitation revealed about 800 PCFS4-TAP enrichment sites on the genome. Some of the enrichment sites are indeed overlapped with the target genes of PCFS4. Analysis of the sequence features of those PCFS4-TAP enrichment sites is on going.

Keywords: Polyadenylation, Plant Development