Protein function: Subunit of the splicing factor SF3A 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. [The UniProt Consortium]
synthetic peptide. The epitope recognized by IHC-00316 maps to a region between residue 300 and 350 of human splicing factor 3a, subunit 1, 120kDa using the numbering given in entry NP_005868.1 (GeneID 10291).