Localization of phospholipase C‐γ1 signaling in caveolae: importance in EGF‐induced phosphoinositide hydrolysis but not in tyrosine phosphorylation

FEBS Letters

Park, Myung Hwan²  Kim, Jae Ho¹  Bae, Sun Sik¹  Ryu, Sung Ho¹  Jang, Il-Ho¹  Lee, Byoung Dae¹  Suh, Pann-Ghill¹ 

[1] Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang 790-784, South Korea;Daewoong R&D Center, 223-23 Sangdaewon-dong, Choongwon-gu, Sungnam, Kyunggi-do 462-120, South Korea

关键词: Phospholipase C-γ1;    Caveola;    Tyrosine phosphorylation;    EGF;    epidermal growth factor;    PLC-γ1;    phospholipase C-γ1;    CM;    caveolin-enriched low-density membrane;    MβCD;    methyl-β-cyclodextrin;    PtdIns;    phosphatidylinositol;    PtdInsP2;    phosphatidylinositol 4;    5-bisphosphate;   

DOI  :  10.1016/S0014-5793(01)02165-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Upon epidermal growth factor treatment, phospholipase C-γ1 (PLC-γ1) translocates from cytosol to membrane where it is phosphorylated at tyrosine residues. Caveolae are small plasma membrane invaginations whose structural protein is caveolin. In this study, we show that the translocation of PLC-γ1 and its tyrosine phosphorylation are localized in caveolae by caveolin-enriched low-density membrane (CM) preparation and immunostaining of cells. Pretreatment of cells with methyl-β-cyclodextrin (MβCD), a chemical disrupting caveolae structure, inhibits the translocation of PLC-γ1 to CM as well as phosphatidylinositol (PtdIns) turnover. However, MβCD shows no effect on tyrosine phosphorylation level of PLC-γ1. Our findings suggest that, for proper signaling, PLC-γ1 phosphorylation has to occur at PtdInsP₂-enriched sites.

【 授权许可】

Unknown