Trichoplein Keratin Filament Binding Protein (TCHP)

The deduced 498-amino acid protein has a calculated molecular mass of 61 kD and shares similarity with trichohyalin (THH) and plectin-1 (PLEC1) over the trichohyalin/plectin homology domain. Immunoblot analysis detected TCHP protein in all tissues examined. In human colon carcinoma cells, TCHP colocalized with KRT8 and KRT18 at the apical cortical membrane and also colocalized with desmoplakin (DSP) in these polarized epithelial cells. Immunohistochemical studies localized TCHP to KRT8/KRT18 filaments in other tissues, including the bile cannicula of hepatocytes, brain, blood vessels, and the apical region of small intestine enterocytes.A 5.5-kb transcript was also detected in heart and skeletal muscle, and a 1.24-kb transcript was detected in heart.