Anti-Yes1 associated transcriptional regulator antibodies are used for the immunodetection of the protein encoded by the YAP1 gene. In humans, the canonical protein has a reported length of 504 amino acid residues and a mass of 54.5 kDa. Its subcellular localization is in the nucleus and cytoplasm. Alternative splicing is reported to yield 9 different isoforms for this protein. A member of the YAP1 protein family, it is a reported transcriptional regulator which can act both as a coactivator and a corepressor and is the critical downstream regulatory target in the Hippo signaling pathway that plays a pivotal role in organ size control and tumor suppression by restricting proliferation and promoting apoptosis. Post-translational modifications have been described, including ubiquitination and phosphorylation. The gene encoding this protein is implicated in Coloboma. Other names for this target antigen include YAP, YAP2, YAP65, YKI, transcriptional coactivator YAP1, and COB1. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.