Matriptase, Recombinant, Human (ST14, SNC19, SNC-19, Epitin, Prostamin, TADG-15, MT-SP1, MTSP1, PRSS

Human matriptase, encoded by the ST14 (suppression of tumorogenicity 14) gene, is also known as tumor associated differentially expressed gene 15 protein/TADG­15) and membrane-type serine protease 1/MT­SP1 (1). Predicted to have a significant role in tumor biology, matriptase may be a novel target for anti­cancer therapy (2). However, expressed in most human epithelia, matriptase is also important in several physiological processes (1). For example, it activates prostasin to initiate a protease cascade that is essential for epidermal differentiation (3), and it converts a single­ chain IGFBP­rp1 into the two­chain form (4)., Matriptase is a type II transmembrane serine protease with a complex modular structure (1). The 855 amino acid (aa) sequence of human matriptase consists of a cytoplasmic tail (aa 1­55), a transmembrane domain (aa 56-76), and an extracellular portion (aa 77-55). The latter contains the following domains: SEA (aa 86-201), two CUBs (aa 214-334 and 340-47), four LDLRAs (aa 452-486, 487-523, 524-560, and 566-603), and a serine protease (aa 615-855). The physiological activation of the single­ chain zymogen requires the cleavage at the SEA domain within the ER or Golgi, association with HAI­1, which facilitates the transport of the protease to the cell surface, and auto­cleavage at QAR­V(615)VGG (1). The activated matriptase is inhibited by HAI­1, and the resulting HAI­1 complex can be shed from the cell surface (1). Description: E. coli-derived recombinant protein corresponding to the sequence Gly596-Val855 of human Matriptase/ST14 protein (NCBI Accession #NP_068813), with an N-terminal Met and 6-His tag. This protein corresponds to the catalytic domain, and is inhibited effectively by rhHAI­1 and rhHAI­2A. The protein was purified, auto-activated and further purified. Activity: Measured by its ability to cleave the fluorogenic peptide substrate Boc­-QAR­-AMC. Specific Activity: >10,000pmoles/min/ug, as measured under the described conditions. See Activity Assay Protocol. Molecular Mass: Predicted: 26kD. , Observed (by SDS-PAGE, reducing conditions): 27kD (major) and minor auto­activation fragments, Storage and Stability: Store at -20°C to -70°C. Unopened product is stable for 6 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.