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Updated: Aug 11, 2026

Imaging G-protein Coupled Receptor (GPCR)-mediated Signaling Events that Control Chemotaxis of Dictyostelium Discoideum
09:40

Imaging G-protein Coupled Receptor (GPCR)-mediated Signaling Events that Control Chemotaxis of Dictyostelium Discoideum

Published on: September 20, 2011

G protein coupling of antigen receptor-stimulated polyphosphoinositide hydrolysis in B cells

M M Harnett1, G G Klaus

  • 1National Institute for Medical Research, London, England.

Journal of Immunology (Baltimore, Md. : 1950)
|May 1, 1988
PubMed

Cross-linking of the IgM and IgD Ag-R on mature B lymphocytes provokes the rapid hydrolysis of phosphatidylinositol 4,5-bisphosphate. We show here that in permeabilized, [3H]inositol-labeled mouse B cells the nonhydrolyzable GTP analogue GTP gamma S induces release of inositol phosphates, including inositol trisphosphate. The response is markedly augmented by the addition of polyclonal anti-Ig or anti-mu or anti-delta mAb. Inositol phosphate release provoked in intact B cells by any of the anti-receptor antibodies was not inhibited by pertussis toxin and only partially inhibited by cholera toxin. The results therefore indicate that both IgM- and IgD-R on B cells are coupled to the polyphosphoinositide-specific phosphodiesterase by one or more G proteins, which have yet to be identified.

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