Cleavage and polyadenylation specificity factor subunit 6 (CPSF6)

Component of the cleavage factor Im (CFIm) complex that functions as an activator of the pre-mRNA 3'-end cleavage and polyadenylation processing necessary for the maturation of pre-mRNA into functional mRNAs (PubMed:9659921, PubMed:8626397, PubMed:14690600, PubMed:29276085). CFIm contributes to the recruitment of multiprotein complexes on specific sequences on the pre-mRNA 3'-end, so called cleavage and polyadenylation signals (pA signs ) (PubMed:9659921, PubMed:8626397, PubMed:14690600).

Many pre-mRNAs contain multiple pA signals, leading to alternative cleavage and polyadenylation (APA) producing mRNAs with variable 3'-end formation (PubMed:23187700, PubMed:29276085). The CFIm complex acts as a key regulator of cleavage and polyadenylation site choice during APA through its binding to 5'- UGUA-3' elements localized in the 3'-untranslated region (UTR) for a massive number of pre-mRNAs (PubMed:20695905, PubMed:29276085).