Many diseases that ultimately lead to blindness are caused by the degeneration of photoreceptor (PR) cells. Cones typically die after rods, with kinetics somewhat dependent upon the particular disease. Rod loss followed by cone loss is also seen in cases where a genetic etiology has not been established, as in some forms of macular degeneration. While humans are able to function quite well without rods, the loss of cone-mediated vision is devastating. The reason(s) that cones die in these cases is unknown. However, since cone loss can be initiated by events that are not intrinsic to cones, these events must include some type of cell-cell interaction, perhaps including the action of a secreted molecule(s). Such a process may be susceptible to interruption through the application of a pharmacological or a cell based therapy. In addition to progressive diseases such as retinitis pigmentosa, there is a mouse model, the cyclin D1 knock-out (KO) mouse, in which degeneration is arrested. The cause of PR death, as well the cause of the arrest, are unknown. This model may provide some insight into how degeneration can be arrested in progressive diseases. We are seeking to use retinal microarrays to define the gene expression changes that accompany PR death in mice, with an emphasis on the events that lead to cone death. In addition, we will characterize the gene expression changes that accompany the arrest of PR degeneration in the cyclin D1 mutant. We further plan to characterize the expression patterns of such genes in normal and pathological tissue. Finally, we will explore the function of some of these genes using genetic approaches in mice. ? ?

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY014466-02
Application #
6696236
Study Section
Special Emphasis Panel (ZRG1-VISC (01))
Program Officer
Dudley, Peter A
Project Start
2003-01-01
Project End
2007-12-31
Budget Start
2004-01-15
Budget End
2004-12-31
Support Year
2
Fiscal Year
2004
Total Cost
$295,313
Indirect Cost
Name
Harvard University
Department
Genetics
Type
Schools of Medicine
DUNS #
047006379
City
Boston
State
MA
Country
United States
Zip Code
02115
Punzo, Claudio; Kornacker, Karl; Cepko, Constance L (2009) Stimulation of the insulin/mTOR pathway delays cone death in a mouse model of retinitis pigmentosa. Nat Neurosci 12:44-52
Chen, Bo; Cepko, Constance L (2009) HDAC4 regulates neuronal survival in normal and diseased retinas. Science 323:256-9
Punzo, Claudio; Cepko, Constance L (2008) Ultrasound-guided in utero injections allow studies of the development and function of the eye. Dev Dyn 237:1034-42
Roesch, Karin; Jadhav, Ashutosh P; Trimarchi, Jeffrey M et al. (2008) The transcriptome of retinal Muller glial cells. J Comp Neurol 509:225-38
Liu, Fang; Jenssen, Tor-Kristian; Trimarchi, Jeff et al. (2007) Comparison of hybridization-based and sequencing-based gene expression technologies on biological replicates. BMC Genomics 8:153
Punzo, Claudio; Cepko, Constance (2007) Cellular responses to photoreceptor death in the rd1 mouse model of retinal degeneration. Invest Ophthalmol Vis Sci 48:849-57
Kuo, Winston Patrick; Liu, Fang; Trimarchi, Jeff et al. (2006) A sequence-oriented comparison of gene expression measurements across different hybridization-based technologies. Nat Biotechnol 24:832-40