The conserved intronic cleavage and polyadenylation site of CstF-77 gene imparts control of 3' end processing activity through feedback autoregulation and by U1 snRNP.

ABSTRACT: The human gene encoding the cleavage/polyadenylation (C/P) factor CstF-77 contains 21 exons. However, intron 3 (In3) accounts for nearly half of the gene region, and contains a C/P site (pA) with medium strength, leading to short mRNA isoforms with no apparent protein products. This intron contains a weak 5' splice site (5'SS), opposite to the general trend for large introns in the human genome. Importantly, the intron size and strengths of 5'SS and pA are all highly conserved across vertebrates, and perturbation of these parameters drastically alters intronic C/P. We found that the usage of In3 pA is responsive to the expression level of CstF-77 as well as several other C/P factors, indicating it attenuates the expression of CstF-77 via a negative feedback mechanism. Significantly, intron

SUBMITTER: Luo W 

PROVIDER: S-EPMC3708835 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature