Provided herein is are polypeptides that include the protease domain of a type II transmembrane serine protease (MTSP) as a single chain. Methods using the polypeptides to identify compounds that modulate the protease activity of an MTSP are provided. Also provided are MTSPs designated MTSP3 and MTSP4...http://www.google.ca/patents/US7700341?utm_source=gb-gplus-sharePatent US7700341 - Nucleic acid molecules encoding transmembrane serine proteases, the encoded proteins and methods based thereon
