Identification of multiple ral gene products in human platelets that account for some but not all of the platelet Gn-proteins.
Polyclonal antibodies raised against specific recombinant low molecular mass GTP-binding proteins were tested for their ability to recognize partially purified human platelet membrane Gn-proteins (i.e. proteins that bind [alpha-32P]GTP on nitrocellulose blots of SDS/polyacrylamide gels). An antiserum against simian ralA protein recognized a 27 kDa human platelet protein with the same apparent molecular mass as the major platelet Gn-protein (Gn27). In further analysis by two-dimensional polyacrylamide gel electrophoresis, the isoelectric focusing step permitted resolution of 12 major Gn-protein forms, seven of 27 kDa (Gn27a-g), one of 26 kDa (Gn26) and four of 24 kDa (Gn24a-d). The ralA antibody reacted strongly with the five most basic Gn27 species (a-e), weakly with Gn26 and not at all with Gn27f, Gn27g or Gn24a-d. We conclude that ral gene products account for some but probably not for all of the platelet Gn-proteins.
Bhullar
R P
RP
Department of Pathology, McMaster University, Hamilton, Ontario, Canada.
Chardin
P
P
Haslam
R J
RJ
D000906:Antibodies / Q000276:immunology; D001792:Blood Platelets / Q000032:analysis* / Q000276:immunology; D003101:Collodion; D015180:Electrophoresis, Gel, Two-Dimensional; D004926:Escherichia coli / Q000235:genetics; D019204:GTP-Binding Proteins / Q000032:analysis* / Q000235:genetics; D015870:Gene Expression; D006160:Guanosine Triphosphate / Q000378:metabolism; D006801:Humans; D007106:Immune Sera / Q000096:biosynthesis; D007525:Isoelectric Focusing; D010980:Platelet Membrane Glycoproteins / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D011506:Proteins / Q000032:analysis* / Q000276:immunology; D011994:Recombinant Proteins / Q000032:analysis / Q000276:immunology
D000906:Antibodies; D007106:Immune Sera; D010980:Platelet Membrane Glycoproteins; D011506:Proteins; D011994:Recombinant Proteins; D006160:Guanosine Triphosphate; D003101:Collodion; D019204:GTP-Binding Proteins