Human PRPF39 is an alternative splicing factor recruiting U1 snRNP to weak 5' splice sites.

ABSTRACT: Human PRPF39 is a homolog of the yeast Prp39 and Prp42 paralogs. We have previously shown that human PRPF39 forms a homodimer that interacts with the CTD of U1C, mirroring the yeast Prp39/Prp42 heterodimer. We demonstrate here that PRPF39 knockdown in HEK293 cells affects many alternative splicing events primarily by reducing the usage of weak 5'ss. Additionally, PRPF39 preferentially binds to a GC-rich RNA, likely at the interface between its NTD and CTD. These data indicate that PRPF39 potentially recruits U1 snRNP to a weak 5' ss, serving as a previously unrecognized alternative splicing factor. We further demonstrate that human TIA1 binds to U1C through its RRM1 and RRM3+Q domains but has no significant binding to PRPF39. Finally, all three human LUC7L isoforms directly interact with U

SUBMITTER: Espinosa S 

PROVIDER: S-EPMC9808567 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature