1. Cell Biology
  2. Structural Biology and Molecular Biophysics

The heteromeric PC-1/PC-2 polycystin complex is activated by the PC-1 N-terminus

  1. Kotdaji Ha
  2. Mai Nobuhara
  3. Qinzhe Wang
  4. Rebecca V Walker
  5. Feng Qian
  6. Christoph Schartner
  7. Erhu Cao
  8. Markus Delling  Is a corresponding author
  1. University of California, San Francisco, United States
  2. University of Utah, United States
  3. University of Maryland School of Medicine, United States
https://doi.org/10.7554/eLife.60684
Share this article
Cite this article
  1. Kotdaji Ha
  2. Mai Nobuhara
  3. Qinzhe Wang
  4. Rebecca V Walker
  5. Feng Qian
  6. Christoph Schartner
  7. Erhu Cao
  8. Markus Delling
(2020)
The heteromeric PC-1/PC-2 polycystin complex is activated by the PC-1 N-terminus
eLife 9:e60684.
https://doi.org/10.7554/eLife.60684
  2. Download BibTeX
  3. Download .RIS

Abstract

Mutations in the polycystin proteins, PC-1 and PC-2, result in autosomal dominant polycystic kidney disease (ADPKD) and ultimately renal failure. PC-1 and PC-2 enrich on primary cilia, where they are thought to form a heteromeric ion channel complex. However, a functional understanding of the putative PC-1/PC-2 polycystin complex is lacking due to technical hurdles in reliably measuring its activity. Here, we successfully reconstitute the PC-1/PC-2 complex in the plasma membrane of mammalian cells and show that it functions as an outwardly rectifying channel. Using both reconstituted and ciliary polycystin channels, we further show that a soluble fragment generated from the N-terminal extracellular domain of PC-1 functions as an intrinsic agonist that is necessary and sufficient for channel activation. We thus propose that autoproteolytic cleavage of the N-terminus of PC-1, a hotspot for ADPKD mutations, produces a soluble ligand in vivo. These findings establish a mechanistic framework for understanding the role of PC-1/PC-2 heteromers in ADPKD and suggest new therapeutic strategies that would expand upon the limited symptomatic treatments currently available for this progressive, terminal disease.

Data availability

Previously published data from PDB was used, available under the accession code 6A70.All data generated or analysed during this study are included in the manuscript and supporting files.

The following previously published data sets were used

Article and author information

Author details

  1. Kotdaji Ha

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Mai Nobuhara

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Qinzhe Wang

    Biochemistry, University of Utah, Salt Lake City, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Rebecca V Walker

    Medicine, University of Maryland School of Medicine, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2473-4303

  5. Feng Qian

    Medicine, University of Maryland School of Medicine, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.

  6. Christoph Schartner

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.

  7. Erhu Cao

    Biochemistry, University of Utah, Salt Lake City, United States
    Competing interests
    The authors declare that no competing interests exist.

  8. Markus Delling

    Department of Physiology, University of California, San Francisco, San Francisco, United States
    For correspondence
    markus.delling@ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9556-2097

Funding

National Institute of General Medical Sciences (R01GM130908)

  • Markus Delling

Fritz Thyssen Stiftung

  • Markus Delling

National Research Foundation of Korea (2019R1A6A3A03033302)

  • Kotdaji Ha

National Institute of Diabetes and Digestive and Kidney Diseases (R01 DK111611)

  • Feng Qian

National Institute of Diabetes and Digestive and Kidney Diseases (U54DK126114)

  • Feng Qian

NIH Research Project Grant (DK110575)

  • Erhu Cao

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

Copyright

© 2020, Ha 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

  • 5,371
    views
  • 851
    downloads
  • 52
    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. Kotdaji Ha
  2. Mai Nobuhara
  3. Qinzhe Wang
  4. Rebecca V Walker
  5. Feng Qian
  6. Christoph Schartner
  7. Erhu Cao
  8. Markus Delling
(2020)
The heteromeric PC-1/PC-2 polycystin complex is activated by the PC-1 N-terminus
eLife 9:e60684.
https://doi.org/10.7554/eLife.60684

Share this article

https://doi.org/10.7554/eLife.60684

Categories and tags

Further reading

    1. Cell Biology

    Novel mechanism for tubular injury in nephropathic cystinosis

    Swastika Sur, Maggie Kerwin ... Minnie M Sarwal
    Research Article

    Understanding the unique susceptibility of the human kidney to pH dysfunction and injury in cystinosis is paramount to developing new therapies to preserve renal function. Renal proximal tubular epithelial cells (RPTECs) and fibroblasts isolated from patients with cystinosis were transcriptionally profiled. Lysosomal fractionation, immunoblotting, confocal microscopy, intracellular pH, TEM, and mitochondrial stress test were performed for validation. CRISPR, CTNS -/- RPTECs were generated. Alterations in cell stress, pH, autophagic turnover, and mitochondrial energetics highlighted key changes in the V-ATPases in patient-derived and CTNS-/- RPTECs. ATP6V0A1 was significantly downregulated in cystinosis and highly co-regulated with loss of CTNS. Correction of ATP6V0A1 rescued cell stress and mitochondrial function. Treatment of CTNS -/- RPTECs with antioxidants ATX induced ATP6V0A1 expression and improved autophagosome turnover and mitochondrial integrity. Our exploratory transcriptional and in vitro cellular and functional studies confirm that loss of Cystinosin in RPTECs, results in a reduction in ATP6V0A1 expression, with changes in intracellular pH, mitochondrial integrity, mitochondrial function, and autophagosome-lysosome clearance. The novel findings are ATP6V0A1’s role in cystinosis-associated renal pathology and among other antioxidants, ATX specifically upregulated ATP6V0A1, improved autophagosome turnover or reduced autophagy and mitochondrial integrity. This is a pilot study highlighting a novel mechanism of tubular injury in cystinosis.

    1. Cell Biology
    2. Developmental Biology

    Rediscovering the rete ovarii, a secreting auxiliary structure to the ovary

    Dilara N Anbarci, Jennifer McKey ... Blanche Capel
    Research Article

    The rete ovarii (RO) is an appendage of the ovary that has been given little attention. Although the RO appears in drawings of the ovary in early versions of Gray’s Anatomy, it disappeared from recent textbooks, and is often dismissed as a functionless vestige in the adult ovary. Using PAX8 immunostaining and confocal microscopy, we characterized the fetal development of the RO in the context of the mouse ovary. The RO consists of three distinct regions that persist in adult life, the intraovarian rete (IOR), the extraovarian rete (EOR), and the connecting rete (CR). While the cells of the IOR appear to form solid cords within the ovary, the EOR rapidly develops into a convoluted tubular epithelium ending in a distal dilated tip. Cells of the EOR are ciliated and exhibit cellular trafficking capabilities. The CR, connecting the EOR to the IOR, gradually acquires tubular epithelial characteristics by birth. Using microinjections into the distal dilated tip of the EOR, we found that luminal contents flow toward the ovary. Mass spectrometry revealed that the EOR lumen contains secreted proteins potentially important for ovarian function. We show that the cells of the EOR are closely associated with vasculature and macrophages, and are contacted by neuronal projections, consistent with a role as a sensory appendage of the ovary. The direct proximity of the RO to the ovary and its integration with the extraovarian landscape suggest that it plays an important role in ovary development and homeostasis.

    1. Cell Biology
    2. Developmental Biology

    Ovarian Biology: Revisiting the rete ovarii

    Yan Zhang, Hua Zhang
    Insight

    Long thought to have little relevance to ovarian physiology, the rete ovarii may have a role in follicular dynamics and reproductive health.