Purification and Amino Terminal Sequencing of Human Melanoma Nerve Growth Factor Receptor

Abstract

The nerve growth factor (NGF) receptor, solubilized with Triton X-100 detergent, has been purified from human melanoma cell line A875. Purification to near-homogeneity was achieved by chromatography on wheat germ agglutinin-agarose, followed by immunoaffinity chromatography on Sepharose columns coupled with anti-NGF receptor monoclonal antibody (MAb). The purified receptor, a 75, 000-dalton protein, retains the capacity to bind NGF as well as anti-receptor MAbs. Final purification was achieved by sodium dodecyl sulfate-polyacryiamide gel electrophoresis. The sequence of amino acid residues at the amino terminus has been determined. Possible sequence homology between the NGF receptor and several other proteins is discussed. Using the purified receptor as immunogen, new MAbs to the NGF receptor have been produced. The NGF receptor was visualized by immunoperoxidase staining in tissue sections of dorsal root ganglia from monkeys.