G protein-dependent signaling

Hicks, J.K. et al., Aspergillus spomlation and mycotoxin production both require inactivation of the FadA G protein-dependent signaling pathway, EM BO J., 16, 4916, 1997. 

Knoblich JA (2001) Asymmetric cell division during animal development. Nat Rev Mol Cell Biol 2 11-20 Kroslak T, Koch T, Kahl E, Hollt V (2001) Human phosphatidylethanolamine-binding protein facihtates heterotrimeric G protein-dependent signaling. J Biol Chem 276 39772-39778 Lankford K, Cypher C, Letoumeau P (1990) Nerve growth cone motility. Curr Opin Cell Biol 2 80-85 Law GJ, Northrop AJ, Mason WT (1993) Rab3-peptide stimulates exocytosis from mast cells via a pertussis toxin-sensitive mechanism. FEBS Lett 333 56-60... 

We consider here some pathologies of the G-protein-dependent signal pathways. Let us first consider the mechanism of action of the cholera toxin, secreted by the intestinal bacterium Vibrio cholera. Cholera is an acute diarrheal disease that can be life threatening. It causes voluminous secretion of electrolytes and fluids from the intestines of infected persons. The cholera toxin, choleragen, is a protein composed of two functional units—a B subunit that binds to gangliosides of the intestinal epithelium and a catalytic A subunit that enters the cell. The A subunit... 

Figure 21.14. Regulatory Cascade for Glycogen Breakdown. Glycogen degradation is stimulated by hormone binding to 7TM receptors. Hormone binding initiates a G-protein-dependent signal-transduction pathway that results in the phosphorylation and activation of glycogen phosphorylase.

Fig. 3. The G-protein dependent signal transduction cycle. The signal transduction unit is represented by R (receptor), G (G protein), and E (effector). G is composed of Ga wifh bound GTP or GDP and of GPy. The acfive and inactive complexes or proteins are shown in black and grey, respectively. S represents the stimulus that triggers the cycle. Proteins interacting in a complex ore linked by hyphens...

Short Circuiting of G-protein-dependent Signalling Pathways... 

Like the oq-ARs, the oq-AR family has unique localization and cellular trafficking properties. Both receptor families have a subtype that is localized to intracellular compartments. Whether this intracellular localization has functional consequences or is an artifact of the methods used to localize these receptors is not known. Unknown also is whether the oq-AR participates in the activation of non-G protein-dependent signaling pathways. However, we do know that acti-... 

Jiao, X., Zhang, N., Xu, X., Oppenheim, J. J., and Jin, T. (2005) Ligand-induced partitioning of human CXCRl chemokine receptors with lipid raft microenvironments facilitates G-protein-dependent signaling. Mol. Cell Biol. 25, 5752-5762. 

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