TULP1 is a gene we identified to cause autosomal recessive retinitis pigmentosa, a hereditary retinal degeneration blinding nearly 1 million people worldwide. The genetic etiology of RP is known for about 50% of cases; however, the biochemical pathways involved in causing the disease much less. The overall objectives of the proposed studies are to explore the physiologic function of TULP1 in the retina and to define the pathologic mechanism leading to photoreceptor degeneration associated with TULP1 mutations. The TULP family consists of four proteins of unknown function, two of which are linked to photoreceptor degeneration. The two specific aims of this application are designed to test the central hypothesis that TULP1 is a component of the molecular machinery involved in the directional translocation of proteins in photoreceptor cells. The first specific aim is to determine the role of TULP1 in photoreceptor transport pathways. This will be accomplished by using immunocytochemistry to determine whether outer segment proteins, intracellular transport proteins and synaptic proteins are mistargeted in tulpt-/- retinas. Immunoelectron microscopy will be performed to determine if the proteins that are incorrectly transported are cargo on the extracellular vesicles in tulpl-/- retinas. The second specific aim is to determine the function of the TULP1/Dynamin-1 interaction identified in photoreceptor cells. This will be done by identifying the functional domains that interact between TULP1 and Dynamin-1 and determining whether TULP1 mutations that cause RP alter the binding between the two proteins. Experiments are also proposed to generate and phenotype mice lacking Dynamin-1 in photoreceptor cells using Cre-loxP mutagenesis. Transport pathways will be evaluated in these mice as described in aim 1. Since little is known about TULP proteins, discovering information regarding the function of TULP proteins should provide knowledge about the pathways involved in photoreceptor degeneration. It is possible that this work could form the foundation for future studies aimed at evaluating therapeutic modalities that might slow, stop, or reverse the course of retinal degeneration.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY016072-03
Application #
7386580
Study Section
Biology and Diseases of the Posterior Eye Study Section (BDPE)
Program Officer
Mariani, Andrew P
Project Start
2006-04-01
Project End
2010-02-28
Budget Start
2008-03-01
Budget End
2009-02-28
Support Year
3
Fiscal Year
2008
Total Cost
$294,038
Indirect Cost
Name
Cleveland Clinic Lerner
Department
Other Basic Sciences
Type
Schools of Medicine
DUNS #
135781701
City
Cleveland
State
OH
Country
United States
Zip Code
44195
Lobo, Glenn P; Au, Adrian; Kiser, Philip D et al. (2016) Involvement of Endoplasmic Reticulum Stress in TULP1 Induced Retinal Degeneration. PLoS One 11:e0151806
Lobo, Glenn P; Ebke, Lindsey A; Au, Adrian et al. (2016) TULP1 Missense Mutations Induces the Endoplasmic Reticulum Unfolded Protein Response Stress Complex (ER-UPR). Adv Exp Med Biol 854:223-30
Ebke, Lindsey A; Pauer, Gayle J T; Willard, Belinda et al. (2016) A Novel Approach to Identify Photoreceptor Compartment-Specific Tulp1 Binding Partners. Adv Exp Med Biol 854:605-11
Grossman, Gregory H; Ebke, Lindsey A; Beight, Craig D et al. (2013) Protein partners of dynamin-1 in the retina. Vis Neurosci 30:129-39
Grossman, Gregory H; Pauer, Gayle J T; Hoppe, George et al. (2012) Isolating photoreceptor compartment-specific protein complexes for subsequent proteomic analysis. Adv Exp Med Biol 723:701-7
Hagstrom, Stephanie A; Watson, Rao F; Pauer, Gayle J T et al. (2012) Tulp1 is involved in specific photoreceptor protein transport pathways. Adv Exp Med Biol 723:783-9
Grossman, Gregory H; Watson, Rao F; Pauer, Gayle J T et al. (2011) Immunocytochemical evidence of Tulp1-dependent outer segment protein transport pathways in photoreceptor cells. Exp Eye Res 93:658-68
Sturgill, Gwen M; Bala, Elisa; Yaniglos, Stacia S et al. (2010) Mutation screen of beta-crystallin genes in 274 patients with age-related macular degeneration. Ophthalmic Genet 31:129-34
Gu, Jiayin; Pauer, Gayle J T; Yue, Xiuzhen et al. (2010) Proteomic and genomic biomarkers for age-related macular degeneration. Adv Exp Med Biol 664:411-7
Pauer, Gayle J T; Sturgill, Gwen M; Peachey, Neal S et al. (2010) Protective effect of paraoxonase 1 gene variant Gln192Arg in age-related macular degeneration. Am J Ophthalmol 149:513-22

Showing the most recent 10 out of 14 publications