Ankyrin Repeat Domain Protein 13C (ANKRD13C)

ANKRD13C, a protein of unknown function, as an interacting partner for the DP receptor for prostaglandin D2. ANKRD13C is a protein associated with the cytosolic side of ER membranes. Co-expression of ANKRD13C with DP initially increased receptor protein levels, whereas siRNA-mediated knockdown of endogenous ANKRD13C decreased them. Pulse-chase experiments indicated that ANKRD13C can promote the biogenesis of DP by inhibiting the degradation of newly synthesized receptors. ANKRD13C also regulated the expression of other GPCRs tested, whereas it did not affect the expression of GFP, GRK2 and VSVG, showing specificity towards G protein-coupled receptors. ANKRD13C acts as a molecular chaperone for G protein-coupled receptors, regulating their biogenesis and exit from the ER.