Mean activation time in situ of one Gt (transducin) molecule

Range ~1 millisec/transducin
Organism vertebrates
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 p.375 right column top paragraphPubMed ID1901231
Primary Source Vuong, T. M., M. Chabre, and L. Stryer. 1984. Millisecond activation of transducin in the cyclic nucleotide cascade of vision. Nature (Lond.). 311: 659-661. & Pepperberg, D. R., M. Kahlert, A. Krause, and K. P. Hofmann. 1988. Photic modulation of a highly sensitive, near-infrared lightscattering signal recorded from intact retinal photoreceptors. Proc. Natl. Acad. Sci. USA. 85: 5531-5535.PubMed ID6090950, 3399504
Comments "For the mean activation time in situ of one Gt molecule, the current estimation is 1 ms per Gt (primary sources). This explosive light-induced activity is in sharp contrast to the very low activity of the system in the dark, as estimated from receptor dark noise (Lamb, 1987)." 1st primary source studied frogs, 2nd primary source studied bovine retina
Entered by Uri M
ID 111000