Variability in Single Photon Responses
نویسندگان
چکیده
منابع مشابه
Variability in Single Photon Responses A Cut in the Gordian Knot of Rod Phototransduction?
hits” is that 10–20 intramolecular rearrangements within the rhodopsin molecule graduate the shutoff of R activMost vertebrates can perform visually guided behaviors ity. This conclusion only deepened the molecular puzzle in lighting that delivers a mere trickle of photons to the posed by their data and those of previous investigations, retina. The toad Bufo bufo, for example, snaps with since ...
متن کاملDeterminants of single photon response variability
The responses to single photon absorptions (quantum bumps) vary randomly in size in Limulus photoreceptors. This variability is a natural consequence of simple chemical reactions involving a small number of molecules. The measured size distributions differ significantly from the exponential distribution predicted by the simplest transduction cascade models, one feature of which is that light-ac...
متن کاملVariability in the Time Course of Single Photon Responses from Toad Rods Termination of Rhodopsin’s Activity
We examined the responses of toad rod photoreceptors to single photons of light. To minimize the effects of variability in the early rising phase, we selected sets of responses that closely matched the rise of the mean single photon response. Responses selected in this way showed substantial variations in kinetics, appearing to peel off from a common time course after different delays. Followin...
متن کاملMechanisms Regulating Variability of the Single Photon Responses of Mammalian Rod Photoreceptors
Variability in the single photon responses of rod photoreceptors limits the accuracy with which the number and timing of photon absorptions are encoded. We investigated how much single photon responses of mammalian rods fluctuate and what mechanisms control these fluctuations. Mammalian rods, like those of toads, generated responses to single photons with trial-to-trial fluctuations 3-4 times s...
متن کاملArrestin competition influences the kinetics and variability of the single-photon responses of mammalian rod photoreceptors.
Reliable signal transduction via G-protein-coupled receptors requires proper receptor inactivation. For example, signals originating from single rhodopsin molecules vary little from one to the next, requiring reproducible inactivation of rhodopsin by phosphorylation and arrestin binding. We determined how reduced concentrations of rhodopsin kinase (GRK1) and/or arrestin1 influenced the kinetics...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Neuron
سال: 1999
ISSN: 0896-6273
DOI: 10.1016/s0896-6273(00)80772-2