Serologically Defined Colon Cancer Antigen 3 (SDCCAG3)

SDCCAG3 protein contains the region similar to the coiled-coil domain of the myosin tail. SDCCAG3 function might be related to protein trafficking and secretion. The expression of the coiledcoil domain as the dominant negative mutant form of SDCCAG3 made the NIH3T3 and HeLa cells resistant to TNF-specific apoptosis. The presentation of TNFR1 at the surface of these cells was reduced, which affected the sensitivity of the cells to the TNF treatment. The inhibition of SDCCAG3 activity by its dominant negative mutant suppressed the protein trafficking and secretion, and decreased TNFR1 presentation on the cell surface. SDCCAG3 is important for protein trafficking and presentation of TNFR1 on the cell surface. Therefore, SDCCAG3 can be viewed as a potential target for modulation of TNF response.