Diffusion coefficient of rhodopsin in rod disk membrane at 20°C

Value 0.5 µm^2/sec
Organism Amphibians
Reference Liebman, P. A., K. R. Parker, and E. A. Dratz. 1987. The molecular mechanism of visual excitation and its relation to the structure and composition of the rod outer segment. Annu. Rev. Physiol. 49: 765- 791. p.766 bottom paragraph & p.774 2nd paragraphPubMed ID3032081
Primary Source [66] Liebman, P. A., Entine, G. 1974. Lateral diffusion of visual pigment in photoreceptor disk membranes. Science 185: 457-59 [104] Poo, M., Cone, R. A. 1974. Lateral diffusion of rhodopsin in the photorecep- tor membrane. Nature 247: 438-42PubMed ID4546260, 4818543
Comments "If one considers the measured lateral diffusion constant of rhodopsin in the membrane plane (5×10^-9 cm^2/sec) (primary sources) and the average separation, collision theory shows that a rhodopsin must collide every 5-10µsec with a neighboring rhodopsin." Research in primary sources conducted on frog and mud puppy.
Entered by Uri M
ID 111001