The dually acylated NH2-terminal domain of gi1alpha is sufficient to target a green fluorescent protein reporter to caveolin-enriched plasma membrane domains. Palmitoylation of caveolin-1 is required for the recognition of dually acylated g-protein alpha subunits in vivo.
The dually acylated NH2-terminal domain of gi1alpha is sufficient to target a green fluorescent protein reporter to caveolin-enriched plasma membrane domains. Palmitoylation of caveolin-1 is required for the recognition of dually acylated g-protein alpha subunits in vivo.
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gi1alpha 的双酰化 NH2 末端结构域足以将绿色荧光蛋白报告基因靶向富含小窝蛋白的质膜结构域。
DOI：
--
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发表时间：
1999
影响因子：
4.8
通讯作者：
M. Parenti
中科院分区：
文献类型：
--
作者：
F. Galbiati;D. Volonté;D. Meani;G. Milligan;D. Lublin;M. Lisanti;M. Parenti
在这里，我们研究了控制G蛋白α亚基靶向质膜的分子机制。为此，我们使用Gi1pha作为双酰化G-蛋白的模型。我们将全长的Gi1α或其NH2末端结构域(残基1-32或1-122)与绿色荧光蛋白(GFP)融合，并分析了这些融合蛋白的亚细胞定位。我们证明，Gi1α的前32个氨基酸足以在体内将GFP靶向质膜上的小窝蛋白富集区，这一点通过与小窝蛋白-1的共分离和免疫共沉淀来证明。有趣的是，当这个32个氨基酸结构域的双酰化被特定的点突变(G2A或C3S)阻止时，所产生的GFP融合蛋白被定位到细胞质中，并被排除在富含小窝蛋白的区域。肉豆蔻酰化但非棕榈酰化(C3S)嵌合体仅部分分割成含有小窝蛋白的组分。然而，两种非酰化GFP融合蛋白(G2A和C3S)不再与小窝蛋白-1共沉淀。综上所述，这些结果表明，Gi1αNH2末端的脂质修饰对于靶向其正确的目的地以及与小窝蛋白-1的相互作用是必不可少的。此外，缺少所有三个棕榈酰化位点(C133S、C143S和C156S)的小窝蛋白-1突变体不能免疫共沉淀这些双酰化的GFP-G蛋白融合。因此，Gi1αNH2末端结构域的双酰化和小窝蛋白-1的棕榈酰化都是稳定并可能调节体内质膜上这种相互作用所必需的。我们的结果首次证明了小窝蛋白-1棕榈酰化在其与信号分子相互作用中的功能作用。
Here we investigate the molecular mechanisms that govern the targeting of G-protein alpha subunits to the plasma membrane. For this purpose, we used Gi1alpha as a model dually acylated G-protein. We fused full-length Gi1alpha or its extreme NH2-terminal domain (residues 1-32 or 1-122) to green fluorescent protein (GFP) and analyzed the subcellular localization of these fusion proteins. We show that the first 32 amino acids of Gi1alpha are sufficient to target GFP to caveolin-enriched domains of the plasma membrane in vivo, as demonstrated by co-fractionation and co-immunoprecipitation with caveolin-1. Interestingly, when dual acylation of this 32-amino acid domain was blocked by specific point mutations (G2A or C3S), the resulting GFP fusion proteins were localized to the cytoplasm and excluded from caveolin-rich regions. The myristoylated but nonpalmitoylated (C3S) chimera only partially partitioned into caveolin-containing fractions. However, both nonacylated GFP fusions (G2A and C3S) no longer co-immunoprecipitated with caveolin-1. Taken together, these results indicate that lipid modification of the NH2-terminal of Gi1alpha is essential for targeting to its correct destination and interaction with caveolin-1. Also, a caveolin-1 mutant lacking all three palmitoylation sites (C133S, C143S, and C156S) was unable to co-immunoprecipitate these dually acylated GFP-G-protein fusions. Thus, dual acylation of the NH2-terminal domain of Gi1alpha and palmitoylation of caveolin-1 are both required to stabilize and perhaps regulate this reciprocal interaction at the plasma membrane in vivo. Our results provide the first demonstration of a functional role for caveolin-1 palmitoylation in its interaction with signaling molecules.
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DOI：
10.1073/pnas.92.20.9407
发表时间：
1995-09-26
影响因子：
11.1
作者：
SARGIACOMO, M;SCHERER, PE;LISANTI, MP
通讯作者：
LISANTI, MP
影响因子：
3.3
作者：
Amy Wolven;Heidi;Okamura;Yael;Rosenblatt;Marilyn;-D.;Resh
通讯作者：
Amy Wolven;Heidi;Okamura;Yael;Rosenblatt;Marilyn;-D.;Resh
通过 G 蛋白 α 亚基的棕榈酰化来抑制大脑 Gz GAP 和其他 RGS 蛋白。
DOI：
10.1126/science.278.5340.1132
发表时间：
1997
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Tu,Y;Wang,J;Ross,EM
通讯作者：
Ross,EM
影响因子：
3.3
作者：
Huang, CF;Hepler, JR;Mumby, SM
通讯作者：
Mumby, SM
生物膜中的鞘脂组织：模型膜的物理研究揭示了什么。
影响因子：
4
作者：
Brown,RE
通讯作者：
Brown,RE