Inactivation of Invs/Nphp2 in renal epithelial cells drives infantile nephronophthisis like phenotypes in mouse

Abstract

Nephronophthisis (NPHP) is a ciliopathy characterized by renal fibrosis and cyst formation, and accounts for a significant portion of end stage renal disease in children and young adults. Currently no targeted therapy is available for this disease. INVS/NPHP2 is one of the 25 NPHP genes identified to date. In mouse, global knockout of Invs leads to renal fibrosis and cysts. However, the precise contribution of different cell types and the relationship between epithelial cysts and interstitial fibrosis remains undefined. Here, we generated and characterized cell-type specific knockout mouse models of Invs, investigated the impact of removing cilia genetically on phenotype severity in Invs mutants and evaluated the impact of the histone deacetylase inhibitor valproic acid (VPA) on Invs mutants. Epithelial specific knockout of Invs in Invsflox/flox;Cdh16-Cre mutant mice resulted in renal cyst formation and severe stromal fibrosis, while Invsflox/flox;Foxd1-Cre mice, where Invs is deleted in stromal cells, displayed no observable phenotypes up to the young adult stage, highlighting a significant role of epithelial-stromal crosstalk. Further, increased cell proliferation and myofibroblast activation occurred early during disease progression and preceded detectable cyst formation in the Invsflox/flox;Cdh16-Cre kidney. Moreover, concomitant removal of cilia partially suppressed the phenotypes of the Invsflox/flox;Cdh16-Cre mutant kidney, supporting a significant interaction of cilia and Invs function in vivo. Finally, VPA reduced cyst burden, decreased cell proliferation and ameliorated kidney function decline in Invs mutant mice. Our results reveal the critical role of renal epithelial cilia in NPHP and suggest the possibility of repurposing VPA for NPHP treatment.

Data availability

No large scale datasets generated. Data analyzed can be found in source data files for figures 1-7, figure 4 figure supplement 1 and figure 7 figure supplement 1.

Article and author information

Author details

  1. Yuanyuan Li

    Department of Genetics, Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Wenyan Xu

    Department of Genetics, Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Svetlana Makova

    Department of Pediatrics, Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Martina Brueckner

    Department of Pediatrics, Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Zhaoxia Sun

    Department of Genetics, Yale University, new haven, United States
    For correspondence
    zhaoxia.sun@yale.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2307-7719

Funding

NIH (R01DK113135)

  • Zhaoxia Sun

NIH (R01HD093608)

  • Zhaoxia Sun

NIH (R35HL145249)

  • Martina Brueckner

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All mouse experiments were performed in Yale University School of Medicine in accordance with Yale University Institutional Animal Care and Use Committee guidelines. Protocols were approved by Yale University Institutional Animal care and Use Committee (Protocol number: 2022-11546).

Copyright

© 2023, Li 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.

Metrics

  • 993
    views
  • 173
    downloads
  • 1
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Yuanyuan Li
  2. Wenyan Xu
  3. Svetlana Makova
  4. Martina Brueckner
  5. Zhaoxia Sun
(2023)
Inactivation of Invs/Nphp2 in renal epithelial cells drives infantile nephronophthisis like phenotypes in mouse
eLife 12:e82395.
https://doi.org/10.7554/eLife.82395

Share this article

https://doi.org/10.7554/eLife.82395

Further reading

    1. Cell Biology
    2. Genetics and Genomics
    Priyanka Das, Alejandro Aballay, Jogender Singh
    Research Article

    Calcineurin is a highly conserved calcium/calmodulin-dependent serine/threonine protein phosphatase with diverse functions. Inhibition of calcineurin is known to enhance the lifespan of Caenorhabditis elegans through multiple signaling pathways. Aiming to study the role of calcineurin in regulating innate immunity, we discover that calcineurin is required for the rhythmic defecation motor program (DMP) in C. elegans. Calcineurin inhibition leads to defects in the DMP, resulting in intestinal bloating, rapid colonization of the gut by bacteria, and increased susceptibility to bacterial infection. We demonstrate that intestinal bloating caused by calcineurin inhibition mimics the effects of calorie restriction, resulting in enhanced lifespan. The TFEB ortholog, HLH-30, is required for lifespan extension mediated by calcineurin inhibition. Finally, we show that the nuclear hormone receptor, NHR-8, is upregulated by calcineurin inhibition and is necessary for the increased lifespan. Our studies uncover a role for calcineurin in the C. elegans DMP and provide a new mechanism for calcineurin inhibition-mediated longevity extension.

    1. Biochemistry and Chemical Biology
    2. Cell Biology
    Julia Shangguan, Ronald S Rock
    Research Article

    Myosin 10 (Myo10) is a motor protein known for its role in filopodia formation. Although Myo10-driven filopodial dynamics have been characterized, there is no information about the absolute number of Myo10 molecules during the filopodial lifecycle. To better understand molecular stoichiometries and packing restraints in filopodia, we measured Myo10 abundance in these structures. We combined SDS-PAGE densitometry with epifluorescence microscopy to quantitate HaloTag-labeled Myo10 in U2OS cells. About 6% of total intracellular Myo10 localizes to filopodia, where it enriches at opposite cellular ends. Hundreds of Myo10s are in a typical filopodium, and their distribution across filopodia is log-normal. Some filopodial tips even contain more Myo10 than accessible binding sites on the actin filament bundle. Live-cell movies reveal a dense cluster of over a hundred Myo10 molecules that initiates filopodial elongation. Hundreds of Myo10 molecules continue to accumulate during filopodial growth, but accumulation ceases when retraction begins. Rates of filopodial elongation, second-phase elongation, and retraction are inversely related to Myo10 quantities. Our estimates of Myo10 molecules in filopodia provide insight into the physics of packing Myo10, its cargo, and other filopodia-associated proteins in narrow membrane compartments. Our protocol provides a framework for future work analyzing Myo10 abundance and distribution upon perturbation.