Light entrainment of the mammalian circadian clock requires input from the retina, which communicates with the suprachiasmatic nucleus (SCN) via the retinohypo-thalamic tract (RHT). This connection is formed by the axonal projections of a small subset of retinal ganglion cells (RGCs). Surprisingly, rod and cone photoreceptors are not required; instead, RGCs that project to the SCN seem to function as autonomous circadian photoreceptors, and exhibit light responses independent of rod- and cone-driven synaptic input. These SCN-projecting RGCs also express melanopsin, a novel opsin-like protein, which has been proposed to be the elusive photopigment of the circadian system. The overall goal of this research is to characterize the biochemical and spectral properties of melanopsin to determine if it mediates the intrinsic light responses of SCN-projecting RGCs. ? ?

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
1F31EY015927-01
Application #
6829979
Study Section
Special Emphasis Panel (ZRG1-CDF-1 (29))
Program Officer
Mariani, Andrew P
Project Start
2004-08-01
Project End
2007-07-31
Budget Start
2004-08-01
Budget End
2005-07-31
Support Year
1
Fiscal Year
2004
Total Cost
$23,522
Indirect Cost
Name
University of Maryland Balt CO Campus
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
061364808
City
Baltimore
State
MD
Country
United States
Zip Code
21250
Walker, Marquis T; Brown, R Lane; Cronin, Thomas W et al. (2008) Photochemistry of retinal chromophore in mouse melanopsin. Proc Natl Acad Sci U S A 105:8861-5