期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1990
卷号：87
期号：2
页码：728-732
DOI：10.1073/pnas.87.2.728
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Myristoylation of seven different alpha subunits of guanine nucleotide-binding regulatory proteins (G proteins) was examined by expressing these proteins in monkey kidney COS cells. Metabolic labeling studies of cells transfected with cytomegalovirus-based expression vectors indicated that [3H]myristate was incorporated into alpha i1, alpha i2, alpha i3, alpha 0, alpha t, and alpha z but not alpha s subunits. The role of myristoylation in the association of alpha subunits with membranes was analyzed by site-directed mutagenesis and by substitution of myristate with a less hydrophobic analog, 10-(propoxy)decanoate (11-oxamyristate). Myristoylation of alpha 0 was blocked when an alanine residue was substituted for its amino-terminal glycine, as was association of the protein with membranes. Substitution of the myristoyl group with 11-oxamyristate affected the cellular distribution of a subset of acylated alpha subunits. The results are consistent with a model wherein the hydrophobic interaction of myristate with the bilayer permits continued association of the protein with the plasma membrane when G-protein alpha subunits dissociate from beta gamma.
