Rapid kinetics of G protein subunit association: A rate-limiting conformational change?
نویسندگان
چکیده
منابع مشابه
Rapid kinetics of G protein subunit association: a rate-limiting conformational change?
G protein subunit association and dissociation are thought to play an important role in signal transduction. We measured alpha beta gamma heterocomplex formation using resonance energy transfer. Fluorescein-labelled alpha(F-alpha) emission was quenched approximately 10% on mixing with eosin-labelled beta gamma(E-beta gamma). Unlabelled beta gamma did not quench F-alpha fluorescence. Stopped-flo...
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Several regulators of G protein signaling (RGS) proteins contain a G protein g-subunit-like (GGL) domain, which, as we have shown, binds to Gb5 subunits. Here, we extend our original findings by describing another GGLdomain-containing RGS, human RGS6. When RGS6 is coexpressed with different Gb subunits, only RGS6 and Gb5 interact. The expression of mRNA for RGS6 and Gb5 in human tissues overlap...
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The association-dissociation kinetics of Escherichia coli MRE 600 “tight” (Type A) ribosomes (30 S + 50 S e 70 S ) for a variety of conditions have been studied in a light-scattering stopped-flow apparatus. The rate constants for the M&’-induced subunit association and 70 S dissociation reactions were 1.7 X lo’ M” s-’ (18 n m M&’) and 0.015 s-l (1 m M@’), respectively. The addition of ribosomal...
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ژورنال
عنوان ژورنال: FEBS Letters
سال: 1994
ISSN: 0014-5793
DOI: 10.1016/0014-5793(94)01212-1