The ability of rod-mediated vision to detect absorption of a handful of photons has led to a set of pre-cise questions about how single photon absorptions are transduced and processed in the retina. These questions have led to a series of breakthroughs in our understanding of the biophysical basis of rod vision, and more generally of the fidelity of neural processing. The behavioral performance of cone vision is similarly impressive, but its relation to biophysical mechanisms is much less clear. This gap in our understanding limits how strongly behavioral results constrain retinal processing of cone-mediated signals. The broad goal of the work proposed here is to elucidate how biophysical mechanisms operating in the rod and cone photoreceptors and the associated retinal circuits enhance and limit visual fidelity. We will focus on three sets of questions: (1) How is rhodopsin's active lifetime controlled to generate single photon responses with low trial-to-trial variability? (2) What sources of noise limit the fidelity of the retinal outputs at low light levels? (3) What is the origin of noise in the responses of cone photoreceptors and what is its impact on the fidelity of the retinal output? We will answer these questions through a combination of electrophysiological recordings of responses in mouse and primate retina and genetic manipulations in mouse retina. Similar issues arise in many other neural circuits;thus the proposed work will improve our general understanding of neural function.

Public Health Relevance

The ability of rod photoreceptors to detect single photons has helped make rod phototransduction the best understood of the many G-protein cascades in biological systems. It also has had direct medical benefits, as we now understand the mechanisms and have potential treatments for several forms of stationary night blindness. We know much less about the retinal readout of rod signals and the generation and processing of cone signals. The long-term aim of the work described here is to help fill this gap in our knowledge. As we have in the past, we will use the technical and conceptual progress made in this work to test transgenic models for visual deficits.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY011850-15
Application #
8212126
Study Section
Biology and Diseases of the Posterior Eye Study Section (BDPE)
Program Officer
Neuhold, Lisa
Project Start
1997-08-01
Project End
2016-01-31
Budget Start
2012-03-01
Budget End
2013-01-31
Support Year
15
Fiscal Year
2012
Total Cost
$224,964
Indirect Cost
$74,964
Name
University of Washington
Department
Physiology
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Ala-Laurila, Petri; Rieke, Fred (2014) Coincidence detection of single-photon responses in the inner retina at the sensitivity limit of vision. Curr Biol 24:2888-98
Puller, Christian; Manookin, Michael B; Neitz, Maureen et al. (2014) Specialized synaptic pathway for chromatic signals beneath S-cone photoreceptors is common to human, Old and New World primates. J Opt Soc Am A Opt Image Sci Vis 31:A189-94
Okawa, Haruhisa; Della Santina, Luca; Schwartz, Gregory W et al. (2014) Interplay of cell-autonomous and nonautonomous mechanisms tailors synaptic connectivity of converging axons in vivo. Neuron 82:125-37
Grimes, William N; Hoon, Mrinalini; Briggman, Kevin L et al. (2014) Cross-synaptic synchrony and transmission of signal and noise across the mouse retina. Elife 3:e03892
Barreiro, Andrea K; Gjorgjieva, Julijana; Rieke, Fred et al. (2014) When do microcircuits produce beyond-pairwise correlations? Front Comput Neurosci 8:10
Grimes, William N; Schwartz, Gregory W; Rieke, Fred (2014) The synaptic and circuit mechanisms underlying a change in spatial encoding in the retina. Neuron 82:460-73
Trenholm, Stuart; McLaughlin, Amanda J; Schwab, David J et al. (2014) Nonlinear dendritic integration of electrical and chemical synaptic inputs drives fine-scale correlations. Nat Neurosci 17:1759-66
Angueyra, Juan M; Rieke, Fred (2013) Origin and effect of phototransduction noise in primate cone photoreceptors. Nat Neurosci 16:1692-700
Cafaro, Jon; Rieke, Fred (2013) Regulation of spatial selectivity by crossover inhibition. J Neurosci 33:6310-20
Schwartz, Gregory W; Rieke, Fred (2013) Controlling gain one photon at a time. Elife 2:e00467

Showing the most recent 10 out of 56 publications