CstF-64 and 3'-UTR cis-element determine Star-PAP specificity for target mRNA selection by excluding PAPα.
Almost all eukaryotic mRNAs have a poly (A) tail at the 3'-end. Canonical PAPs (PAPα/γ) polyadenylate nuclear pre-mRNAs. The recent identification of the non-canonical Star-PAP revealed specificity of nuclear PAPs for pre-mRNAs, yet the mechanism how Star-PAP selects mRNA targets is still elusive. Moreover, how Star-PAP target mRNAs having canonical AAUAAA signal are not regulated by PAPα is unclear. We investigate specificity mechanisms of Star-PAP that selects pre-mRNA targets for polyadenylation. Star-PAP assembles distinct 3'-end processing complex and controls pre-mRNAs independent of PAPα. We identified a Star-PAP recognition nucleotide motif and showed that suboptimal DSE on Star-PAP target pre-mRNA 3'-UTRs inhibit CstF-64 binding, thus preventing PAPα recruitment onto it. Altering 3'-UTR cis-elements on a Star-PAP target pre-mRNA can switch the regulatory PAP from Star-PAP to PAPα. Our results suggest a mechanism of poly (A) site selection that has potential implication on the regulation of alternative polyadenylation.
Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Trivandrum 695014, India.
Divya T
DT
Kandala
Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Trivandrum 695014, India.
Nimmy
N
Mohan
Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Trivandrum 695014, India.
Vivekanand
V
A
Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Trivandrum 695014, India.
Sudheesh
S
A P
Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Trivandrum 695014, India.
Reshmi
R
G
Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Trivandrum 695014, India laishram@rgcb.res.in.
Rakesh S
RS
Laishram
D020413:3' Untranslated Regions; D051017:Apoptosis Regulatory Proteins / Q000235:genetics; D001665:Binding Sites; D002460:Cell Line; D039241:Cleavage Stimulation Factor; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics; D024101:Mitochondrial Proteins; D009154:Mutation; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000235:genetics; D059372:Nucleotide Motifs; D009713:Nucleotidyltransferases; D011061:Poly A; D011062:Polynucleotide Adenylyltransferase / Q000235:genetics / Q000378:metabolism*; D012322:RNA Precursors / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D012045:Regulatory Sequences, Nucleic Acid; D013379:Substrate Specificity
D020413:3' Untranslated Regions; D051017:Apoptosis Regulatory Proteins; C096820:BIK protein, human; C474466:CSTF2T protein, human; D039241:Cleavage Stimulation Factor; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D012322:RNA Precursors; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D011061:Poly A; D016660:NAD(P)H Dehydrogenase (Quinone); C447479:NQO1 protein, human; D009713:Nucleotidyltransferases; C586325:TUT1 protein, human; D011062:Polynucleotide Adenylyltransferase