InterPro domain: IPR038737

This entry includes animal splicing factor 3B subunit 1 (SF3B1, also known as SAP 155) and its homologues such as Hsh155 from budding yeasts [ 1 ] and Prp10 from fission yeasts [ 2 ]. SF3B1 is a component of the splicing factor SF3B complex, which is important for anchoring the spliceosome to precursor mRNA. SF3B1 binds to pre-mRNA on both sides of the intron branch site region [ 3 ]. This subunit is required for 'A' splicing complex assembly (formed by the stable binding of U2 snRNP to the branchpoint sequence in pre-mRNA) and 'E' splicing complex assembly [ 4 ].

1. Functional Cus1p is found with Hsh155p in a multiprotein splicing factor associated with U2 snRNA. Mol. Cell. Biol. 20, 2176-85
2. The fission yeast prp10(+) gene involved in pre-mRNA splicing encodes a homologue of highly conserved splicing factor, SAP155. Nucleic Acids Res. 26, 5662-9
3. A novel U2 and U11/U12 snRNP protein that associates with the pre-mRNA branch site. EMBO J. 20, 4536-46
4. Crystal structure of a core spliceosomal protein interface. Proc. Natl. Acad. Sci. U.S.A. 103, 1266-71