Phosphorylation of HS1, GAP-associated p190 and a novel GAP-associated p60 protein by cross-linking of Fc gamma RIIIA.
Human Fc gamma receptor IIIA (hFc gamma RIIIA) cDNA was introduced into mouse macrophage/monocyte cell line P388D1, and several stable cell clones expressing hFc gamma RIIIA were isolated. This facilitated the study of the biological function of Fc gamma RIIIA in monocytes/macrophages. The cloned cells showed the high phagocytic activity mediated by hFc gamma-RIIIA, while the original P388D1 cells did not. In order to examine the phosphorylation of proteins involved in hFc gamma RIIIA signal transduction, these receptors were stimulated by cross-linking. The cross-linking of hFc gamma RIIIA induced a rapid increase in tyrosine phosphorylation of several proteins, including PLC-gamma 1, Syk, HS1, and p21rasGAP-associated p190 and p60 proteins. Immunoblotting with a polyclonal antibody specific for the GAP-associated p62 protein, which was originally found in fibroblasts and is homologous with an RNA-binding protein, revealed that the p60 phosphorylated after cross-linking of hFc gamma RIIIA seemed to represent a novel GAP-associated protein unrelated to the known GAP-associated p62 protein, which was also present in the P388D1 cells.
Zeng
H
H
Tokyo Institute for Immunopharmacology, Inc.
Yoshida
T
T
Kurosaki
T
T
Yamamura
H
H
Oshima
A
A
Kitamura
D
D
Watanabe
T
T
Morikawa
M
M
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D001798:Blood Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002999:Clone Cells; D003432:Cross-Linking Reagents; D004268:DNA-Binding Proteins; D020690:GTPase-Activating Proteins; D020662:Guanine Nucleotide Exchange Factors; D006801:Humans; D008264:Macrophages; D051379:Mice; D009000:Monocytes; D009687:Nuclear Proteins / Q000302:isolation & purification / Q000378:metabolism*; D010587:Phagocytosis; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism*; D010766:Phosphorylation; D017452:Receptors, IgG / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D012097:Repressor Proteins; D014162:Transfection; D010738:Type C Phospholipases / Q000378:metabolism
C074560:ARHGAP35 protein, human; D048868:Adaptor Proteins, Signal Transducing; C513041:Arhgap35 protein, mouse; D001798:Blood Proteins; D003432:Cross-Linking Reagents; D004268:DNA-Binding Proteins; D020690:GTPase-Activating Proteins; D020662:Guanine Nucleotide Exchange Factors; C061909:HCLS1 protein, human; D009687:Nuclear Proteins; D010750:Phosphoproteins; D017452:Receptors, IgG; D011994:Recombinant Proteins; D012097:Repressor Proteins; D010738:Type C Phospholipases