G protein transducers

FIGURE 7.1 Martin Rodbell s conception of the role of the G-protein transducer in the activation of adenylate cyclase by glucagon. (From Birnbaumer, L., FASEB J., 4, 3178, 1990. With permission.)... 

Gilman AG. 1987. G proteins transducers of receptorgenerated signals. Annu Rev Biochem 56 615-649. 

Gilman, A. G., G proteins Transducers of receptor-generated signals. Ann. Rev. Biochem. 56 615-650, 1987. 

Relatively few types of G proteins transduce the signals from a vast number of receptors. Each member of the heterotrimeric G protein family must, therefore, be capable of interacting with many different receptors. Additionally, many receptors are capable of activating multiple different G proteins. Although many interfacial contacts between these proteins have been described, the connections that define the coupling between receptors and specific G proteins remain unclear. 

Heterotrimeric G proteins transduce a variety of signals generated by interactions with hormones, growth factors, neurotransmitters, and other molecules with cell surface receptors. G proteins are activated in endothelial cells as a result of strain and increased strain-rate phosphorylation of ERK 1/2, which requires G proteins. G proteins are believed to be involved in mechanochemical transduction through adhesion coupled cell mechanosensing. 

A. G. Gilman. G proteins transducers of receptor-generated signals. RevBiochem, 56, 615-649,1987. 

Trimeric G proteins transduce signals from coupled cell-surface receptors to associated effector proteins, which are either enzymes that form second messengers or cation channel proteins (see Table 13-1). 

G proteins are heterotrimeric in structure with the subunits (in decreasing size) designated as a, p, and y. At least 13 types of G proteins have been identified, which are divided among four families, Gg, G, Gq, and G 2- Individual G proteins transduce the receptor activation signal via one of a number of... 

Table 4.1. G-Protein Transducers and Second Messengers G-Protein Transducer FamilySecond Messenger System...

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