Transmembrane Protease, Serine 5 (TMPRSS5)

TMPRSS5 encodes a protein that belongs to the serine protease family. The deduced 457-amino acid protein shows a simple type II transmembrane structure consisting of a short N-terminal cytoplasmic domain, a transmembrane domain, a stem region with a scavenger receptor-like domain, a serine protease domain that includes the essential his, asp, and ser catalytic triad, and an extracellular region containing 5 N-glycosylation sites. TMPRSS5 shares 38.5 to 44.5% sequence similarity with other transmembrane serine proteases. Northern blot analysis detected a 2.3-kb transcript specifically in brain. Western blot analysis indicated a mass of 30 kD for the recombinant protein and an apparent mass of 53 kD for the fully glycosylated form expressed in human brain and cerebral spinal fluid.