| Range |
>3,000 transducins/rhodopsin
|
| Organism |
Toad Bufo marinus |
| Reference |
Kahlert, M., and K. P. Hofmann. 1991. Reaction rate and collision efficiency of the rhodopsin-transducin system in intact retinal rods. Biophys. J. 59: 375–386 DOI :10.1016/S0006-3495(91)82231-7 p.375 left column bottom paragraphPubMed ID1901231
|
| Primary Source |
Dawis, S. M., R. M. Graeff, R. A. Heyman, T. F. Walseth, and N. D. Goldberg. 1988. Regulation of cyclic GMP metabolism in toad photoreceptors. J. Biol. Chem. 263: 8771-8785.PubMed ID2837463
|
| Method |
(From primary source:) "...the mechanisms subserving the regulation of photoreceptor cGMP metabolism were assessed in intact red rod photoreceptors of isolated toad retinas by examining metabolic responses to different photic stimuli." |
| Comments |
"...[researchers] have explored the dynamics of the activation reaction of the rod G-protein (transducin, Gt). In intact rod cells, one single molecule of the
light-activated receptor rhodopsin (R*) can turn over >3,000 copies of Gt (primary source). The well-known fast lateral and rotational diffusion of rhodopsin, and presumably of Gt, in the disc membrane affords sufficiently frequent collisions for a high speed of activation." |
| Entered by |
Uri M |
| ID |
110989 |