Transmembrane Protease, Serine 11A (TMPRSS11A)

ECRG1 caused senescence-like changes in transfected mouse NIH3T3 cells, including changes in cell morphology, cell cycle arrest at the G1/S phase, and impaired cell proliferation. Transfected cells also stained positive for a cellular senescence marker. Telomerase activity was markedly decreased in ECRG1-expressing cells, and expression of p21 (CDKN1A) was increased.

The deduced 418-amino acid protein has characteristics of a membrane-anchored serine protease, including the his-asp-ser catalytic triad. RT-PCR and Northern blot analysis showed ECRG1 expression in normal esophagus, liver, colon, and lung, with downregulated expression in tumors, especially esophageal squamous cell carcinomas.