功能
function:Subunit of the splicing factor SF3B required for 'A' complex assembly formed by the stable binding of U2 snRNP to the branchpoint sequence (BPS) in pre-mRNA. Sequence independent binding of SF3A/SF3B complex 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. Belongs also to the minor U12-dependent spliceosome, which is involved in the splicing of rare class of nuclear pre-mRNA intron.,similarity:Belongs to the RSE1 family.,subunit:Identified in the spliceosome C complex, at least composed of AQR, ASCC3L1, C19orf29, CDC40, CDC5L, CRNKL1, DDX23, DDX41, DDX48, DDX5, DGCR14, DHX35, DHX38, DHX8, EFTUD2, FRG1, GPATC1, HNRPA1, HNRPA2B1, HNRPA3, HNRPC, HNRPF, HNRPH1, HNRPK, HNRPM, HNRPR, HNRPU, KIAA1160, KIAA1604, LSM2, LSM3, MAGOH, MORG1, PABPC1, PLRG1, PNN, PPIE, PPIL1, PPIL3, PPWD1, PRPF19, PRPF4B, PRPF6, PRPF8, RALY, RBM22, RBM8A, RBMX, SART1, SF3A1, SF3A2, SF3A3, SF3B1, SF3B2, SF3B3, SFRS1, SKIV2L2, SNRPA1, SNRPB, SNRPB2, SNRPD1, SNRPD2, SNRPD3, SNRPE, SNRPF, SNRPG, SNW1, SRRM1, SRRM2, SYF2, SYNCRIP, TFIP11, THOC4, U2AF1, WDR57, XAB2 and ZCCHC8. Component of splicing factor SF3B which is composed of at least eight subunits; SF3B1/SAP155/SF3B155, SF3B2/SAP145/SF3B145, SF3B3/SAP130/SF3B130, SF3B4/SAP49/SF3B49, SF3B14A, PHF5A/SF3B14B, SF3B10 and SF3B125. SF3B associates with the splicing factor SF3A and a 12S RNA unit to form the U2 small nuclear ribonucleoproteins complex (U2 snRNP). Interaction between SF3B3 and SF3B1 is tighter than the interaction between SF3B3 and SF3B2. Associates with the STAGA transcription coactivator-HAT complex. Interacts with SUPT3H.,
