| Function | Component of the 17S U2 SnRNP complex of the spliceosome, a large ribonucleoprotein complex that removes introns from transcribed pre-mRNAs. The 17S U2 SnRNP complex (1) directly participates in early spliceosome assembly and (2) mediates recognition of the intron branch site during pre-mRNA splicing by promoting the selection of the pre-mRNA branch-site adenosine, the nucleophile for the first step of splicing. Within the 17S U2 SnRNP complex, SF3B1 is part of the SF3B subcomplex, which is required for 'A' complex assembly formed by the stable binding of U2 snRNP to the branchpoint sequence in pre-mRNA. Sequence independent binding of SF3A and SF3B subcomplexes upstream of the branch site is essential, it may anchor U2 snRNP to the pre-mRNA. May also be involved in the assembly of the 'E' complex. Also acts as a component of the minor spliceosome, which is involved in the splicing of U12-type introns in pre-mRNAs. Together with other U2 snRNP complex components may also play a role in the selective processing of microRNAs (miRNAs) from the long primary miRNA transcript, pri-miR-17-92. |
| Protein Name | Splicing Factor 3b Subunit 1Pre-Mrna-Splicing Factor Sf3b 155 Kda SubunitSf3b155Spliceosome-Associated Protein 155Sap 155 |
| Database Links | Reactome: R-HSA-5250924Reactome: R-HSA-72163Reactome: R-HSA-72165 |
| Cellular Localisation | NucleusNucleus SpeckleDuring MitosisTransiently Dispersed From The Nuclear Speckles To The Cytoplasm |
| Alternative Protein Names | Splicing Factor 3b Subunit 1 proteinPre-Mrna-Splicing Factor Sf3b 155 Kda Subunit proteinSf3b155 proteinSpliceosome-Associated Protein 155 proteinSap 155 proteinSF3B1 proteinSAP155 protein |
Information sourced from Uniprot.org
