title: Substrate specificity of rat DESC4, a type II transmembrane serine protease.
abstract: Type II transmembrane serine proteases (TTSPs) are involved in important physiological processes, such as pro-hormone processing, cellular signaling, host immune defense, and cancer development. The diversity of functions is reflected by the multidomain architecture of these proteases, which are composed of a variety of functional domains in addition to the catalytic domain. Recently, we identified rat DESC4, a member of the HAT/DESC1-like subfamily of TTSPs. Intriguingly, DESC4 gene expression is confined to few tissues including gustatory papillae. In the current publication we present the purification of the catalytic domain of recombinant rat DESC4. Subsequently, the catalytic domain was subjected to a refolding procedure. During refolding we observed endogenous catalytic activity leading to smaller fragments, which were analyzed by peptide sequencing. The identified cleavage-sites are typical for trypsin-like serine proteases. For further analyses a homology-based model of the DESC4 catalytic domain was generated enabling us to investigate protease-substrate interaction in more detail.
authors.affiliation: German Institute of Human Nutrition Potsdam-Rehbruecke, Dept. Molecular Genetics, 14558 Nuthetal, Germany. behrens@dife.de
authors.forename: Maik
authors.initials: M
authors.lastname: Behrens
authors.forename: Friedrich
authors.initials: F
authors.lastname: Buck
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Meyerhof
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D020134:Catalytic Domain / Q000502:physiology; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017510:Protein Folding; D051381:Rats; D011994:Recombinant Proteins / Q000378:metabolism; D012697:Serine Endopeptidases / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D008565:Membrane Proteins; D011994:Recombinant Proteins; D012697:Serine Endopeptidases; C497696:Tmprss11g protein, rat