Anti-B cell receptor-associated protein 29 antibodies are protein reagents that detect specific antigens. The B cell receptor-associated protein 29 antigen is another term for the human protein B cell receptor associated protein 29, encoded by the BCAP29 gene. The protein is believed to play a role in anterograde transport of membrane proteins from the endoplasmic reticulum to the Golgi. Canonically, it has an amino acid length of 241 residues and a mass of 28.3 kilodaltons. Its subcellular localization is in the ER and it is widely expressed in many tissue types. The B cell receptor-associated protein 29 protein is a member of the BCAP29/BCAP31 protein family.