Allosteric behavior in transducin activation mediated by rhodopsin. Initial rate analysis of guanine nucleotide exchange.
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چکیده
منابع مشابه
Allosteric behavior in transducin activation mediated by rhodopsin. Initial rate analysis of guanine nucleotide exchange.
Photolyzed rhodopsin acts in a catalytic manner to mediate the exchange of GTP for GDP bound to transducin. We have analyzed the steady-state kinetics of this activation process in order to determine the molecular mechanism of interactions between rhodopsin, transducin, and guanine nucleotides. Initial velocities (Vo) of the exchange reaction catalyzed by rhodopsin were measured for various tra...
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Heterotrimeric G-protein activation by an agonist-stimulated G-protein coupled receptor (R*) requires the propagation of structural signals from the receptor interacting surfaces to the guanine nucleotide-binding pocket. Employing high-resolution NMR methods, we are probing heterotrimer-associated and rhodopsin-stimulated changes in an isotope-labeled G-protein alpha-subunit (G(alpha)). A key a...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1987
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(18)61411-5