Evidence that a protein-protein interaction 'hot spot' on heterotrimeric G protein βγ subunits is used for recognition of a subclass of effectors
Evidence that a protein-protein interaction 'hot spot' on heterotrimeric G protein βγ subunits is used for recognition of a subclass of effectors
复制标题
DOI：
10.1093/emboj/20.4.767
复制
发表时间：
2001-02-15
期刊：
影响因子：
11.4
通讯作者：
Smrcka, AV
中科院分区：
文献类型：
--
作者：
Scott, JK;Huang, SF;Smrcka, AV
为了了解与 G 蛋白 β γ 亚基结合的要求，使用固定化生物素化 py 作为靶标筛选噬菌体展示的随机肽库。选定的肽根据其序列特征分为四个不同的家族。一组（I组）具有明显的保守基序，该基序与磷脂酶Cβ（PLCβ）衍生的肽以及与G蛋白β亚基结合的光导素中的短基序具有显着同源性，其他组与I组序列具有较弱的序列同源性或没有同源性。来自最强共识组的合成肽可阻断 G 蛋白 β γ 亚基对 PLC 的激活，该肽不会阻断 β γ 介导的电压门控钙通道抑制，并且对 β γ 介导的 Gs 刺激的 I 型腺苷酸环化酶抑制影响不大。竞争实验表明，所有四个家族的肽均与 β-γ 上的单个位点结合。这些肽可能与效应子亚类所使用的 β γ 亚基表面上的蛋白质-蛋白质相互作用“热点”结合。
To understand the requirements for binding to G protein beta gamma subunits, phage-displayed random peptide libraries were screened using immobilized biotinylated py as the target. Selected peptides were grouped into four different families based on their sequence characteristics. One group (group I) had a clear conserved motif that has significant homology to peptides derived from phospholipase C beta (PLC beta) and to a short motif in phosducin that binds to G protein beta subunits, The other groups had weaker sequence homologies or no homology to the group I sequences. A synthetic peptide from the strongest consensus group blocked activation of PLC by G protein beta gamma subunits, The peptide did not block beta gamma -mediated inhibition of voltage-gated calcium channels and had little effect on beta gamma -mediated inhibition of Gs-stimulated type I adenylate cyclase. Competition experiments indicated that peptides from all four families bound to a single site on beta gamma. These peptides may bind to a protein-protein interaction 'hot spot' on the surface of beta gamma subunits that is used by a subclass of effecters.