Squamous cell carcinoma antigen recognized by T cells (SART1), also known as U4/U6. U5 tri-snRNP-associated 110 kDa protein, is a ubiquitously expressed protein that is involved in mRNA splicing and the regulation of cell proliferation. It has been identified as regulator of c-FLIP and drug-induced activation of caspase 8. The SART1 gene encodes two proteins, the SART1(800) protein is located in the nucleus of the majority of proliferating cells, while the SART1(259) protein is located in the cytosol of epithelial cancers. Genetic variation in the SART1 gene may be associated with breast cancer development. This antibody recognizes the endogenous 800-amino acid SART1, which migrates with an apparent molecular mass of 110 kDa in SDS-PAGE. (PMID: 22027693; 9449708; 19377877; 11350945)