In broad terms, our goal is to determine the molecular nature of membrane-related events which underly visual excitation in the rod cells of the vertebrate retina. The most immediate objectives of this proposal can be specifically grouped as follows: (i) Chemical synthesis, isotopic labelling with 2H, and structural studies employing nuclear magnetic resonance (NMR) of highly polyunsaturated phospholipids. Such polyunsaturated phospholipids are found in extremely high levels in the vertebrate retinal rod outer segment (ROS) disk membranes; yet, little is known of their structural or functional properties. It is possible that such polyunsaturated phospholipids may play a specific but as yet undertermined role in the process of vision. (ii) Application and development of new solid-state NMR techniques for structural studies of phospholipid bilayers. High-resolution solid-state 13C NMR spectra will be obtained and new NMR relaxation methods will be developed to obtain information regarding the orientational ordering and molecular dynamics of phospholipids in both native and recombinant membranes containing rhodopsin. (iii) The photochemical function of rhodopsin in recombinant membranes will be studied using flash photolysis techniques as well as recently developed enzymatic assays. The role of structural variables such as the phospholipid acyl chain length and the degree and position of the acyl chain unsaturation on the function of rhodopsin will be systematically investigated. Using these methods, and following the approach outlined in this proposal, it is our intent to provide a fairly complete physical picture of rhodopsin-lipid interactions and their relationship to function during the proposed RCDA project period. Throughout this work, emphasis will be placed upon correlation of the structural properties of the rhodopsion-containing membranes with selected aspects of their vision-related function.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Modified Research Career Development Award (K04)
Project #
5K04EY000255-02
Application #
3072817
Study Section
Biophysics and Biophysical Chemistry B Study Section (BBCB)
Project Start
1985-02-01
Project End
1990-01-31
Budget Start
1986-02-01
Budget End
1987-01-31
Support Year
2
Fiscal Year
1986
Total Cost
Indirect Cost
Name
University of Virginia
Department
Type
Schools of Arts and Sciences
DUNS #
001910777
City
Charlottesville
State
VA
Country
United States
Zip Code
22904
Aravind, Penmatsa; Wistow, Graeme; Sharma, Yogendra et al. (2008) Exploring the limits of sequence and structure in a variant betagamma-crystallin domain of the protein absent in melanoma-1 (AIM1). J Mol Biol 381:509-18
Nag, Nabanita; Peterson, Katherine; Wyatt, Keith et al. (2007) Endogenous retroviral insertion in Cryge in the mouse No3 cataract mutant. Genomics 89:512-20
Purkiss, Andrew G; Bateman, Orval A; Wyatt, Keith et al. (2007) Biophysical properties of gammaC-crystallin in human and mouse eye lens: the role of molecular dipoles. J Mol Biol 372:205-22
Ellena, J F; Pates, R D; Brown, M F (1986) 31P NMR spectra of rod outer segment and sarcoplasmic reticulum membranes show no evidence of immobilized components due to lipid-protein interactions. Biochemistry 25:3742-8
Brown, M F; Williams, G D (1985) Membrane NMR: a dynamic research area. J Biochem Biophys Methods 11:71-81