A new animal model for retinitis pigmentosa was recently generated by targeted disruption of the inhibitory gamma subunit of rod cGMP-PDE gene (Pdeg). In this proposal, germline gene therapy will first be used to rescue the photoreceptors survival and function. Different mutant PDE-gammas will then be used in attempts to modify photoreceptor function and degeneration. Toward this end, homologous recombination in combination with Cre/lox site-specific recombination will be used to generate mutant alleles in the mouse germ line. These new technologies should allow more temporally- and spatially-controlled expression of mutant PDE-gamma than with traditional transgenic approaches. Selective point mutations engineered in the endogenous PDE-gamma gene locus are predicted to alter the catalytic control of PDE core; the phosphorylation control of PDE-gamma's inhibitory action on the PDE catalytic core; or the binding of the PDE-gamma to transducin. These PDE-gamma mutant lines will yield insights into the mechanism of vertebrate phototransduction in vivo.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY011510-02
Application #
2838370
Study Section
Visual Sciences C Study Section (VISC)
Project Start
1997-12-01
Project End
2000-11-30
Budget Start
1998-12-01
Budget End
1999-11-30
Support Year
2
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Columbia University (N.Y.)
Department
Ophthalmology
Type
Schools of Medicine
DUNS #
167204994
City
New York
State
NY
Country
United States
Zip Code
10032
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Tsang, S H; Yamashita, C K; Doi, K et al. (2001) In vivo studies of the gamma subunit of retinal cGMP-phophodiesterase with a substitution of tyrosine-84. Biochem J 353:467-74
Salchow, D J; Gouras, P; Doi, K et al. (1999) A point mutation (W70A) in the rod PDE-gamma gene desensitizing and delaying murine rod photoreceptors. Invest Ophthalmol Vis Sci 40:3262-7
Ekesten, B; Gouras, P; Moschos, M (1998) Cone properties of the light-adapted murine ERG. Doc Ophthalmol 97:23-31