CALR3 Full-Length MS Protein Standard (NP_659483), Labeled with [U- 13C6, 15N4]-L-Arginine and [U- 13C6, 15N2]-L-Lysine, was produced in human 293 cells (HEK293) with fully chemically defined cell culture medium to obtain incorporation efficiency at Creative-Proteomics. The protein encoded by this gene belongs to the calreticulin family, members of which are calcium-binding chaperones localized mainly in the endoplasmic reticulum. This protein is also localized to the endoplasmic reticulum lumen, however, its capacity for calcium-binding may be absent or much lower than other family members. This gene is specifically expressed in the testis, and may be required for sperm fertility. Mutation in this gene has been associated with familial hypertrophic cardiomyopathy.