期刊
JOURNAL OF RECEPTORS AND SIGNAL TRANSDUCTION
卷 27, 期 5-6, 页码 335-352出版社
TAYLOR & FRANCIS INC
DOI: 10.1080/10799890701684142
关键词
TRH receptor; G(q)/G(11) protein; Ca2+ response; beta-cyclodextrin; cholesterol; lipid raft
We monitored the radioligand-binding characteristics of thyrotropin-releasing hormone (TRH) receptors, functional activity of G(q/11)alpha proteins, and functional status of the whole signaling cascade in HEK293 expressing high levels of TRH receptors and G(11)alpha. Our analyses indicated that disruption of plasma membrane microdomains by cholesterol depletion did not markedly influence the binding parameters of TRH receptors, but it altered efficacy of signal transduction. The functional coupling between TRH receptor and G(q/11)alpha was assessed by agonist-stimulated [S-35]GTP gamma S binding, and results of these measurements pointed out to significantly lower potency of TRH to mediate G protein activation in the plasma membrane fraction isolated from cholesterol-depleted cells; there was a shift in sensitivity by one order of magnitude to the higher concentrations. A markedly lower sensitivity to stimulation with TRH was also observed in our experiments dealing with determination of hormone-induced Ca2+ response. These data suggest that the intact structure of plasma membranes is an important optimum signal transduction. initiated by TRH receptors and mediated by G(q/11)alpha proteins.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据