Drosophila stimulatory G protein alpha subunit activates mammalian adenylyl cyclase but interacts poorly with mammalian receptors: implications for receptor-G protein interaction.

AUTOR(ES)

Quan, F

RESUMO

Heterotrimeric guanine nucleotide binding proteins (G proteins) transduce signals from cell-surface receptors to intracellular effector proteins. Two forms of stimulatory G protein (Gs) alpha-like subunit have been described in Drosophila melanogaster. To examine the function of these subunits we have used vaccinia virus vectors to express both proteins in cyc- cells, a murine S49 cell line deficient for Gs alpha activity. Receptor-independent activation of each Drosophila Gs alpha has demonstrated that both forms are capable of activating mammalian adenylyl cyclase and thus have the activity expected of stimulatory G proteins. However, the Drosophila Gs alpha subunits interact poorly with mammalian Gs-coupled receptors. These observations have helped to identify a region of high variability in Gs alpha proteins that may be important for receptor interactions.

Documentos Relacionados

• Receptor-G protein coupling is established by a potential conformational switch in the beta gamma complex.
• Identification of a mutation in the gene encoding the alpha subunit of the stimulatory G protein of adenylyl cyclase in McCune-Albright syndrome.
• The cDNA sequence of the alpha-subunit of the Chinese hamster adenylate cyclase-stimulatory G-protein.
• Effect of association with adenylyl cyclase-associated protein on the interaction of yeast adenylyl cyclase with Ras protein.
• G protein subunits and the stimulation of phospholipase C by Gs-and Gi-coupled receptors: Lack of receptor selectivity of Galpha(16) and evidence for a synergic interaction between Gbeta gamma and the alpha subunit of a receptor activated G protein.