%0 Journal Article
%T Prostasin: An Epithelial Sodium Channel Regulator
%A Shakti Aggarwal
%A Pradeep K. Dabla
%A Sarika Arora
%J Journal of Biomarkers
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/179864
%X Prostasin is a glycophosphatidylinositol-anchored protein which is found in prostate gland, kidney, bronchi, colon, liver, lung, pancreas, and salivary glands. It is a serine protease with trypsin-like substrate specificity which was first purified from seminal fluid in 1994. In the last decade, its diverse roles in various biological and physiological processes have been elucidated. Many studies done to date suggest that prostasin is one of several membrane peptidases regulating epithelial sodium channels in mammals. A comprehensive literature search was conducted from the websites of Pubmed Central, the US National Library of Medicine¡¯s digital archive of life sciences literature and the National Library of Medicine. The data was also assessed from journals and books that published relevant articles in this field. Understanding the mechanism by which prostasin and its inhibitors regulate sodium channels has provided a new insight into the treatment of hypertension and some other diseases like cystic fibrosis. Prostasin plays an important role in epidermal growth factor receptor (EGFR) signal modulation. Extracellular proteases have been implicated in tumor metastasis and local tissue invasion because of their ability to degrade extracellular matrices. 1. Introduction Prostasin (also known as channel activating protease 1) is a novel extracellular serine protease with trypsin-like activity which cleaves synthetic substrates in vitro, preferentially at carboxy-terminal side of arginine residue. The serine proteases constitute one of the largest classes of proteolytic enzymes and have evolved to perform specialized functions. The catalytic triad that is essential for the enzymatic activity of prostasin is a histidine, aspartic acid, and serine sequence. Prostasin belongs to the classical serine protease family, with homology to trypsin, chymotrypsin, and kallikrein, and has a trypsin-like substrate specificity [1¨C3]. Trypsin-like serine proteases typically are synthesized as inactive zymogens that are activated by a single endoproteolytic cleavage. This group of enzymes often acts in either single or complex, highly regulated zymogen cascades to control important biological processes, such as coagulation, fibrinolysis, blood pressure, and digestion. The enzyme activation of prostasin occurs via cleavage of the proprotein to produce a light chain and a heavy chain that are disulfide linked [3]. Prostasin belongs to a distinct family of genes in syntenic regions of human chromosome 16p13.3/11.2 and mouse chromosomes 7 and 17 that includes tryptase- (TPSG),
%U http://www.hindawi.com/journals/jbm/2013/179864/