Iron homeostasis: casting new roles

摘要

The type II transmembrane serine proteases (TTSPs) are a family of membrane-associated proteases sharing several structural motifs, including a short cytoplasmic amino-terminal tail, a single-pass transmembrane domain, a central region containing modular domains that may participate in protein-protein interactions, and a carboxy-terminal catalytic domain. TTSPs differ in their patterns of tissue expression, suggesting that the different family members may have distinct physiological roles. Matriptase-2, encoded by the gene Tmprss6, is a TTSP family member primarily expressed in the liver. Although in vitro studies have shown that matriptase-2 is capable of degrading several components of the extracellular matrix, the in vivo role of matriptase-2 remained to be elucidated.