title: Melanoblast/melanocyte early marker (MelEM) is a glutathione S-transferase subunit.
abstract: We have biochemically characterized the antigen recognized by the melanoblast/melanocyte early marker (MelEM) monoclonal antibody (Mab) which labels early melanoblasts and melanocytes in the avian embryo [1]. While among the neural crest derivatives MelEM Mab is strictly specific for the melanocytic lineage, some endodermal derivatives such as hepatocytes react with this Mab. Since MelEM Mab immunoprecitates a protein of the same relative mass from both liver extracts and melanocytes, we immunopurified MelEM protein from liver extract of quail embryos at 10 days of incubation. The N-terminal sequence of this protein being blocked, we determined three internal peptide sequences. Our study reveals that the MelEM protein is an Alpha class subunit of glutathione S-transferase which is common to hepatocytes and to neural crest-derived pigment cells during their differentiation.
authors.affiliation: Institut d'Embryologie Cellulaire et Moléculaire, CNRS, Collège de France, Nogent-sur-Marne.
authors.forename: V
authors.initials: V
authors.lastname: Nataf
authors.forename: P
authors.initials: P
authors.lastname: Mercier
authors.forename: B
authors.initials: B
authors.lastname: De Néchaud
authors.forename: J C
authors.initials: JC
authors.lastname: Guillemot
authors.forename: J
authors.initials: J
authors.lastname: Capdevielle
authors.forename: F
authors.initials: F
authors.lastname: Lapointe
authors.forename: N M
authors.initials: NM
authors.lastname: Le Douarin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D015415:Biomarkers; D015153:Blotting, Western; D002478:Cells, Cultured; D002846:Chromatography, Affinity; D003370:Coturnix; D004591:Electrophoresis, Polyacrylamide Gel; D004625:Embryo, Nonmammalian; D005241:Feathers / Q000166:cytology / Q000201:enzymology; D005982:Glutathione Transferase / Q000032:analysis / Q000096:biosynthesis* / Q000302:isolation & purification; D017403:In Situ Hybridization; D008099:Liver / Q000166:cytology* / Q000201:enzymology; D046911:Macromolecular Substances; D008544:Melanocytes / Q000166:cytology* / Q000201:enzymology; D051379:Mice; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D051381:Rats; D017386:Sequence Homology, Amino Acid
chemical_list: D000911:Antibodies, Monoclonal; D015415:Biomarkers; D046911:Macromolecular Substances; D015345:Oligonucleotide Probes; D005982:Glutathione Transferase