Human Phospho-STAT3 (S727) Antibody

PI16 (Peptidase Inhibitor 16) is a variable molecular weight (MW) member of the CRISP family of proteins. It is expressed by cardiomyocytes and serves as an autocrine negative growth regulator. Mature mouse PI16 is a type I transmembrane protein 469 amino acids (aa) in length. The extracellular region includes all but the C‑terminal 21 amino acids. A soluble form of PI16 is known. Although its predicted MW is 50 kDa, it runs anomalously at 70 kDa (unmodified) in SDS‑PAGE. With glycosylation, it appears to be 100‑110 kDa in size. Three potential variants exist. One shows a deletion of aa 51‑124, a second shows a 9 aa extension at the N‑terminus, and a third shows a deletion of aa 191‑452. Over aa 1‑464, mouse PI16 shares 86% and 61% aa identity with rat and human PI16, respectively.