TACSTD2 is a cell surface glycoprotein receptor. It is a single-pass type I membrane protein containing one thyroglobulin type-1 domain, an epidermal growth factor-like repeat, a phosphatidylinositol binding site, and tyrosine phosphorylation sites near the C-terminus. It plays a role in transducing intracellular calcium signals. It is expressed in trophoblast cells, cornea, and multi-stratified epithelia. It is also highly expressed in several types of tumors and is involved in regulating the growth of carcinoma cells.