Disrupting the ciliary gradient of active Arl3 affects rod photoreceptor nuclear migration
- University of Michigan-Ann Arbor, United States
- University of North Carolina at Chapel Hill, United States
- Duke University, United States
Abstract
The small GTPase Arl3 is important for the enrichment of lipidated proteins to primary cilia, including the outer segment of photoreceptors. Human mutations in the small GTPase Arl3 cause both autosomal recessive and dominant inherited retinal dystrophies. We discovered that dominant mutations result in increased active G-protein—Arl3-D67V has constitutive activity and Arl3-Y90C is fast cycling—and their expression in mouse rods resulted in a displaced nuclear phenotype due to an aberrant Arl3-GTP gradient. Using multiple strategies, we go on to show that removing or restoring the Arl3-GTP gradient within the cilium is sufficient to rescue the nuclear migration defect. Together, our results reveal that an Arl3 ciliary gradient is involved in proper positioning of photoreceptor nuclei during retinal development.
Data availability
All data generated or analyzed for this study are included in the manuscript and supporting files; source data files have been provided for all figures. The MATLAB code used for normalization of nuclear position is available at https://github.com/DrWessler/Disrupting-the-ciliary-gradient-of-active-Arl3-affects-rod-photoreceptor-nuclear-migration/.
Article and author information
Author details
Jillian N Pearring
Funding
Research to Prevent Blindness (Career Development Award)
- Jillian N Pearring
E. Matilda Ziegler Foundation for the Blind (Research Award)
- Jillian N Pearring
National Eye Institute (T32 Postdoctoral Award)
- Amanda M Travis
This work was supported by a NIH P30 grant EY007003 (University of Michigan), NIH T32 grant EY013934 (A.M.T.), Matilda E. Ziegler Research Award (J.N.P.), Career Development Award (J.N.P.), an Unrestricted Grant (University of Michigan) from Research to Prevent Blindness.
Ethics
Animal experimentation: This study was performed at the University of Michigan, following strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals and accreditation from the Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC) International. Mice were handled following protocols approved by the Institutional Animal Care and Use Committees at the University of Michigan (registry number A3114-01). All mice were housed in a 12/12-hour light/dark cycle with free access to food and water and every effort was made to minimize suffering.
Copyright
© 2023, Travis et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Disrupting the ciliary gradient of active Arl3 affects rod photoreceptor nuclear migration
eLife 12:e80533.
https://doi.org/10.7554/eLife.80533
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