title: A 43 kDa form of the GTP-binding protein Gi3 in human erythrocytes.
abstract: Purified preparations of human erythrocyte G-proteins contain a 43 kDa pertussis toxin substrate which appears to be the alpha-subunit of a heterotrimeric GTP-binding protein. The 43 kDa protein is recognized by antisera that are sequence-specific for peptides encoding a sequence common to all 39-53 kDa G-protein alpha-subunits. G alpha o-specific antiserum did not recognize 43 or 40-41 kDa alpha-subunits. AS/6, which recognizes the alpha i proteins, recognized 43 kDa as well as 40-41 kDa proteins. Of the three antisera specific for individual members of the alpha i family, only the Gi3-specific antiserum recognized the 43 kDa erythrocyte G-protein. However, 40-41 kDa forms of all three alpha is are present. These observations indicate that human erythrocytes contain a novel 43 kDa form of Gi3.
authors.affiliation: Department of Pharmacology, Mount Sinai School of Medicine, City University of New York, NY 10029.
authors.forename: D J
authors.initials: DJ
authors.lastname: Carty
authors.forename: R
authors.initials: R
authors.lastname: Iyengar
mesh_terms: D001345:Autoradiography; D004912:Erythrocytes / Q000032:analysis*; D019204:GTP-Binding Proteins / Q000097:blood* / Q000235:genetics / Q000276:immunology; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D037342:Pertussis Toxin; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D007106:Immune Sera; D010566:Virulence Factors, Bordetella; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins