Selectivity in Signal Transduction Determined by γ Subunits of Heterotrimeric G Proteins
Abstract
Various heterotrimeric guanine nucleotide-binding proteins have been identified on the basis of the individual subtypes of their α subunits. The βγ complexes, composed of β and γ subunits, remain tightly associated under physiological conditions and have been assumed to constitute a common pool shared among various guanosine triphosphate (GTP)-binding (G) protein heterotrimers. Particular α and β subunit subtypes participate in the signal transduction processes between somatostatin or muscarinic receptors and the voltage-sensitive L-type calcium channel in rat pituitary GH_3 cells. Among γ subunits the γ_3 subtype was found to be required for coupling of the somatostatin receptor to voltage-sensitive calcium channels, whereas the γ_4 subtype was found to be required for coupling of the muscarinic receptor to those channels.
- Publication:
-
Science
- Pub Date:
- February 1993
- DOI:
- 10.1126/science.8094261
- Bibcode:
- 1993Sci...259..832K