A cysteine‐11 to serine mutant of Gα12 impairs activation through the thrombin receptor

FEBS Letters

Ponimaskin, Evgeni¹  Schultz, Günter²  Schmidt, Michael F.G.¹  Harteneck, Christian² 

[1] Institut für Immunologie und Molekularbiologie, Freie Universität Berlin, City Campus Veterinary Faculty, Luisenstrasse 56, D-10117 Berlin, Germany;Institut für Pharmakologie, Freie Universität Berlin, Thielallee 69/73, D-14195 Berlin, Germany

关键词: Palmitoylation;    G-protein;    Gα12;    Thrombin receptor;   

DOI  :  10.1016/S0014-5793(98)00638-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have recently reported that Gα₁₂ is acylated with palmitic acid [Veit et al., FEBS Lett. 339 (1994) 160–164]. Here we identify cysteine 11 as the sole palmitoylation site and assess the function of Gα₁₂ palmitoylation after expression of wild type and acylation-deficient mutant in insect cells. Our experimental approach yielded the following results. (1) Palmitoylation of Gα₁₂ has no influence on the subunit interactions. (2) Palmitoylation promotes membrane binding of Gα₁₂ when this protein is expressed alone. Membrane attachment of the heterotrimer occurs independent of the presence of fatty acids in Gα₁₂. (3) Assays for agonist-stimulated binding of [³⁵S]GTPγS after expression of the human thrombin receptor (PAR1) along with Gα₁₂ and the βγ subunits revealed a 70% inhibition with the palmitoyl-deficient mutant.

【 授权许可】

Unknown