Open AccessG sα contains an unidentified covalent modification that increases its affinity for adenylyl cyclase
Author(s) -
Christiane Kleuss,
Alfred G. Gilman
Publication year - 1997
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.94.12.6116
Subject(s) - adenylyl cyclase , palmitoylation , adcy10 , adcy9 , cysteine , chemistry , covalent bond , gs alpha subunit , myristoylation , biochemistry , stereochemistry , camp dependent pathway , g protein , enzyme , receptor , organic chemistry , phosphorylation
Many G protein α subunits are dually acylated with myristate and palmitate or are palmitoylated on more than one cysteine residue near their N termini. The Gα protein that activates adenylyl cyclase, αs , is not myristoylated but can be reversibly palmitoylated. It appears that αs contains another, as-yet-unidentified covalent modification that decreases its apparent dissociation constant for adenylyl cyclase from 50 nM to <0.5 nM. This modification is at or near the N terminus of the protein and is hydrophobic. Palmitoylation of native αs does not account for its high affinity for adenylyl cyclase.