Characterization of p40/GPR69A as a peripheral membrane protein related tothe lantibiotic synthetase component C

The 40 kDa erythrocyte membrane protein p40/GPR69A, previously assigned to the G-protein-coupled receptor superfamily, was now identified by peptide-a ntibodies and characterized as a loosely associated peripheral membrane pro tein. This result is in striking contrast to the proposed seven-transmembra ne protein structure and function and therefore we wish to correct our prev ious proposal. p40 is located at the cytoplasmic side of the membrane and i s neither associated with the cytoskeleton nor lipid rafts. Refined sequenc e analysis revealed that p40 is related to the LanC family of bacterial mem brane-associated proteins which are involved in the biosynthesis of antimic robial peptides. Therefore, we rename p40 to LanC-like protein 1 (LANCL1) a nd suggest that it may play a similar role as a peptide-modifying enzyme co mponent in eukaryotic cells, (C) 2000 Academic Press.