heterotrimeric G-protein GTPase

Hydrolases;
Acting on acid anhydrides;
Acting on GTP to facilitate cellular and subcellular movement

GTP phosphohydrolase (signalling)

GTP + H2O = GDP + phosphate [RN:R00335]

R00335

GTP [CPD:C00044];
H2O [CPD:C00001]

This group comprises GTP-hydrolysing systems, where GTP and GDP alternate in binding. This group includes stimulatory and inhibitory G-proteins such as Gs, Gi, Go and Golf, targetting adenylate cyclase and/or K+ and Ca2+ channels; Gq stimulating phospholipase C; transducin activating cGMP phosphodiesterase; gustducin activating cAMP phosphodiesterase. Golf is instrumental in odour perception, transducin in vision and gustducin in taste recognition. At least 16 different alpha subunits (39-52 kDa), 5 beta subunits (36 kDa) and 12 gamma subunits (6-9 kDa) are known.

1  [PMID:7834744]

Neer EJ.

Heterotrimeric G proteins: organizers of transmembrane signals.

Cell. 80 (1995) 249-57.

Homo sapiens [GN:hsa]

2  [PMID:9242920]

Sprang SR.

G protein mechanisms: insights from structural analysis.

Annu. Rev. Biochem. 66 (1997) 639-78.

Homo sapiens [GN:hsa], Bos taurus [GN:bta], Thermus thermophilus, Thermus aquaticus

3  [PMID:9188484]

Bondarenko VA, Desai M, Dua S, Yamazaki M, Amin RH, Yousif KK, Kinumi T, Ohashi M, Komori N, Matsumoto H, Jackson KW, Hayashi F, Usukura J, Lipkin VM, Yamazaki A.

Residues within the polycationic region of cGMP phosphodiesterase gamma subunit crucial for the interaction with transducin alpha subunit. Identification by endogenous ADP-ribosylation and site-directed mutagenesis.

J. Biol. Chem. 272 (1997) 15856-64.

Rana catesbiana, Rana grylio

4  [PMID:9671782]

Ming D, Ruiz-Avila L, Margolskee RF.

Characterization and solubilization of bitter-responsive receptors that couple to gustducin.

Proc. Natl. Acad. Sci. U. S. A. 95 (1998) 8933-8.

Bos taurus [GN:bta]