Diacylglycerol kinase gamma interacts with and activates beta2-chimaerin, a Rac-specific GAP, in response to epidermal growth factor.
Diacylglycerol kinase (DGK)gamma was shown to act as an upstream suppressor of Rac1. Here we report that, in COS7 cells stimulated with epidermal growth factor (EGF), DGKgamma specifically interacts and co-localizes at the plasma membrane with beta2-chimaerin, a GTPase-activating protein (GAP) for Rac. Moreover, DGKgamma enhanced EGF-dependent translocation of beta2-chimaerin to the plasma membrane. Interestingly, DGKgamma markedly augmented EGF-dependent GAP activity of beta2-chimaerin through its catalytic action. These results indicate that DGKgamma is a novel regulator of beta2-chimaerin, and thus suggest that beta2-chimaerin is an effector molecule, linking DGKgamma functionally with Rac1.
Yasuda
Satoshi
S
Department of Biochemistry, Sapporo Medical University School of Medicine, South-1, West-17, Chuo-ku, Sapporo 060-8556, Japan.
Kai
Masahiro
M
Imai
Shin-Ichi
S
Kanoh
Hideo
H
Sakane
Fumio
F
D000818:Animals; D001483:Base Sequence; D001693:Biological Transport, Active; D019556:COS Cells; D002462:Cell Membrane / Q000378:metabolism; D002522:Chlorocebus aethiops; D006224:Cricetinae; D019852:Diacylglycerol Kinase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D051379:Mice; D041681:NIH 3T3 Cells; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D020830:rac1 GTP-Binding Protein / Q000378:metabolism
D009363:Neoplasm Proteins; D034741:RNA, Small Interfering; D011994:Recombinant Proteins; C079844:beta-chimaerin; D004815:Epidermal Growth Factor; D019852:Diacylglycerol Kinase; D020830:rac1 GTP-Binding Protein