Work

The effect of activating ligands on the intrinsic fluorescence of guanine nucleotide-binding regulatory proteins.

Year: 1987

Type: article

Abstract: The intensity of the tryptophan fluorescence of the alpha subunits of guanine nucleotide-binding regulatory proteins increases when they bind guanosine 5'-O-(3-thio)triphosphate (GTY gamma S). The kinetics of the fluorescence enhancement and of the measured binding of [35S]GTP gamma S are well correlated. The addition of Mg2+ to the nucleotide-bound proteins causes a further, rapid increase in the fluorescence intensity. Similar effects result from exposure of the proteins to F- and Mg2+, and the required concentration of F- is reduced by the inclusion of Al3+. It is presumed that the more highly fluorescent state of the G protein alpha subunits represents their active conformation.

Source: Journal of Biological Chemistry

DOI: 10.1016/s0021-9258(19)75849-9

Authors: T Higashijima, K M Ferguson, P C Sternweis, E M Ross, M D Smigel, A G Gilman

Institution: The University of Texas Southwestern Medical Center

Language: English

Topic: Receptor Mechanisms and Signaling

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: hybrid

Estimated APC paid: $3,430

Funder: National Institute of General Medical Sciences