Transmembrane Protease, Serine 6 (TMPRSS6)

TMPRSS6 shares 35% sequence identity with human matriptase/ST14 and spinesin/TMPRSS5, and 84.3% identity with mouse Tmprss6. It contains structural features characteristic of type II serine proteinases, including a short hydrophobic domain, a type II transmembrane sequence, 2 CUB domains, 3 LDL receptor repeats, and a C-terminal catalytic domain with structural hallmarks of serine proteinases. A potential phosphorylation domain is present at the cytoplasmic tail. Sequence alignment of the catalytic domains of TMPRSS6 and other type II serine proteinase family members permitted the identification of several conserved domains. Northern blot analysis of multiple human tissues revealed expression of a 3.5-kb TMPRSS6 transcript exclusively in fetal and adult liver.