Format

Send to

Choose Destination
FEBS Lett. 1997 Mar 3;404(1):100-4.

A cell-density sensing factor regulates the lifetime of a chemoattractant-induced G alpha-GTP conformation.

Author information

1
Howard Hughes Medical Institute, Department of Biochemistry and Cell Biology, Houston, TX 77251-1892, USA.

Abstract

Starving Dictyostelium discoideum cells monitor the local density of other starving cells by simultaneously secreting and sensing CMF. CMF regulates signal transduction through the chemoattractant cAMP receptor, cAR1. cAR1 activates a heterotrimeric G protein by stimulating G alpha 2 to release GDP and bind GTP. We show here that the rate of cAMP-stimulated GTP hydrolysis in membranes from cells exposed to CMF is roughly 4 times slower than in membranes from untreated cells, even though the rate of GTP binding is the same. This hydrolysis is abolished in cells lacking G alpha 2. Our data thus suggest that CMF regulates cAMP signal transduction in part by prolonging the lifetime of the G alpha 2-GTP complex.

PMID:
9074646
DOI:
10.1016/s0014-5793(97)00104-x
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center