University of Massachusetts Medical School Faculty Publications
UMMS Affiliation
Program in Molecular Medicine
Publication Date
2017-05-25
Document Type
Article Preprint
Disciplines
Cell Biology | Congenital, Hereditary, and Neonatal Diseases and Abnormalities | Genetic Phenomena
Abstract
Diverse human ciliopathies, including nephronophthisis (NPHP), Meckel syndrome (MKS) and Joubert syndrome (JBTS), can be caused by mutations affecting components of the transition zone, a ciliary domain near its base. The transition zone controls the protein composition of the ciliary membrane, but how it does so is unclear. To better understand the transition zone and its connection to ciliopathies, we defined the arrangement of key proteins in the transition zone using two-color stochastic optical reconstruction microscopy (STORM). This mapping revealed that NPHP and MKS complex components form nested rings comprised of nine-fold doublets. The NPHP complex component RPGRIP1L forms a smaller diameter transition zone ring within the MKS complex rings. JBTS-associated mutations in RPGRIP1L disrupt the architecture of the MKS and NPHP rings, revealing that vertebrate RPGRIP1L has a key role in organizing transition zone architecture. JBTS-associated mutations in TCTN2, encoding an MKS complex component, also displace proteins of the MKS and NPHP complexes from the transition zone, revealing that RPGRIP1L and TCTN2 have interdependent roles in organizing transition zone architecture. To understand how altered transition zone architecture affects developmental signaling, we examined the localization of the Hedgehog pathway component SMO in human fibroblasts derived from JBTS-affected individuals. We found that diverse ciliary proteins, including SMO, accumulate at the transition zone in wild type cells, suggesting that the transition zone is a way station for proteins entering and exiting the cilium. JBTS-associated mutations in RPGRIP1L disrupt SMO accumulation at the transition zone and the ciliary localization of SMO. We propose that the disruption of transition zone architecture in JBTS leads to a failure of SMO to accumulate at the transition zone, disrupting developmental signaling in JBTS.
Keywords
cell biology, ciliopathies, Joubert syndrome, transition zone, mutations, proteins, stochastic optical reconstruction microscopy, STORM, TCTN2, Meckel syndrome, nephronophthisis
Rights and Permissions
The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. It is made available under a CC-BY-NC 4.0 International license.
DOI of Published Version
10.1101/142042
Source
bioRxiv 142042; doi: https://doi.org/10.1101/142042. Link to preprint on bioRxiv service.
Journal/Book/Conference Title
bioRxiv
Repository Citation
Shi X, Garcia III G, Van De Weghe JC, University of California, San Francisco, Pazour GJ, Doherty D, Huang B, Reiter J. (2017). Super-Resolution Microscopy Reveals That Disruption Of Ciliary Transition Zone Architecture Is A Cause Of Joubert Syndrome. University of Massachusetts Medical School Faculty Publications. https://doi.org/10.1101/142042. Retrieved from https://escholarship.umassmed.edu/faculty_pubs/1552
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Included in
Cell Biology Commons, Congenital, Hereditary, and Neonatal Diseases and Abnormalities Commons, Genetic Phenomena Commons