Anti-U1AP antibodies are used in antigen-specific immunodetection in biological samples. The target U1AP is a known alias name of the protein small nuclear ribonucleoprotein U1 subunit 70, encoded by the SNRNP70 gene in humans. This 437-amino acid residue protein is a known component of the spliceosomal U1 snRNP, which is essential for recognition of the pre-mRNA 5' splice-site and the subsequent assembly of the spliceosome. It is localized to the nucleus of the cell and features phosphorylated post-translational modifications. It is reported to be widely expressed in many tissue types. Other synonyms for U1AP include RNPU1Z, RPU1, and SNRP70.