Serine protease HTRA1

Serine protease HTRA1 is an enzyme that in humans is encoded by the HTRA1 gene. The HTRA1 protein is composed of four distinct protein domains. They are from amino-terminus to carboxyl-terminus an Insulin-like growth factor binding domain, a kazal domain, a trypsin-like peptidase domain and a PDZ domain.

This gene encodes a member of the trypsin family of serine proteases. This protein is a secreted enzyme that is proposed to regulate the availability of insulin-like growth factors (IGFs) by cleaving IGF-binding proteins. It has also been suggested to be a regulator of cell growth.

Mutations of this gene are responsible for the development of CARASIL, a genetic form of cerebral vasculopathy.