PUBLICATION
The exocyst is required for photoreceptor ciliogenesis and retinal development
- Authors
- Lobo, G.P., Fulmer, D., Guo, L., Zuo, X., Dang, Y., Kim, S.H., Su, Y., George, K., Obert, E., Fogelgren, B., Nihalani, D., Norris, R.A., Rohrer, B., Lipschutz, J.H.
- ID
- ZDB-PUB-170722-5
- Date
- 2017
- Source
- The Journal of biological chemistry 292(36): 14814-14826 (Journal)
- Registered Authors
- Kim, Seok-Hyung, Lobo, Glenn, Su, Yanhui
- Keywords
- exocycst, exocyst, exocytosis, eye, photoreceptor, primary cilium, retinal degeneration
- MeSH Terms
-
- Animals
- Cilia/metabolism*
- Exocytosis*
- Mice
- Mice, Inbred C57BL
- Mutation
- Photoreceptor Cells, Vertebrate/metabolism*
- Photoreceptor Cells, Vertebrate/pathology
- Retina/metabolism*
- Retina/pathology
- Vesicular Transport Proteins/deficiency
- Vesicular Transport Proteins/metabolism
- Zebrafish
- PubMed
- 28729419 Full text @ J. Biol. Chem.
Citation
Lobo, G.P., Fulmer, D., Guo, L., Zuo, X., Dang, Y., Kim, S.H., Su, Y., George, K., Obert, E., Fogelgren, B., Nihalani, D., Norris, R.A., Rohrer, B., Lipschutz, J.H. (2017) The exocyst is required for photoreceptor ciliogenesis and retinal development. The Journal of biological chemistry. 292(36):14814-14826.
Abstract
We previously have shown that the highly conserved eight-protein exocyst trafficking complex is required for ciliogenesis in kidney tubule cells. We hypothesized here that ciliogenic programs are conserved across organs and species. To determine whether renal primary ciliogenic programs are conserved in the eye, and to characterize the function and mechanisms by which the exocyst regulates eye development in zebrafish, we focused on exoc5, a central component of the exocyst complex, by analyzing both exoc5 zebrafish mutants, and photoreceptor-specific Exoc5 knock-out mice. Two separate exoc5 mutant zebrafish lines phenocopied exoc5 morphants and, strikingly, exhibited a virtual absence of photoreceptors, along with abnormal retinal development and cell death. Because the zebrafish mutant was a global knockout, we also observed defects in several ciliated organs, including the brain (hydrocephalus), heart (cardiac edema), and kidney (disordered and shorter cilia). exoc5 knockout increased phosphorylation of the regulatory protein Mob1, consistent with Hippo pathway activation. exoc5 mutant zebrafish rescue with human EXOC5 mRNA completely reversed the mutant phenotype. We accomplished photoreceptor-specific knockout of Exoc5 with our Exoc5 fl/fl mouse line crossed with a rhodopsin-Cre driver line. In Exoc5 photoreceptor-specific knock-out mice, the photoreceptor outer segment structure was severely impaired at 4 weeks of age, although a full-field electroretinogram indicated a visual response was still present. However, by 6 weeks, visual responses were eliminated. In summary, we show that ciliogenesis programs are conserved in the kidneys and eyes of zebrafish and mice and that the exocyst is necessary for photoreceptor ciliogenesis and retinal development, most likely by trafficking cilia and outer-segment proteins.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping