1. Structural Biology and Molecular Biophysics

Cooperative unfolding of distinctive mechanoreceptor domains transduces force into signals

  1. Lining Ju
  2. Yunfeng Chen
  3. Lingzhou Xue
  4. Xiaoping Du
  5. Cheng Zhu  Is a corresponding author
  1. Georgia Institute of Technology, United States
  2. Pennsylvania State University, United States
  3. University of Illinois at Chicago, United States
https://doi.org/10.7554/eLife.15447
Share this article
Cite this article
  1. Lining Ju
  2. Yunfeng Chen
  3. Lingzhou Xue
  4. Xiaoping Du
  5. Cheng Zhu
(2016)
Cooperative unfolding of distinctive mechanoreceptor domains transduces force into signals
eLife 5:e15447.
https://doi.org/10.7554/eLife.15447
  2. Download BibTeX
  3. Download .RIS

Abstract

How cells sense their mechanical environment and transduce forces into biochemical signals is a crucial yet unresolved question in mechanobiology. Platelets use receptor glycoprotein Ib (GPIb), specifically its α subunit (GPIbα), to signal as they tether and translocate on von Willebrand factor (VWF) of injured arterial surfaces against blood flow. Force slows VWF-GPIbα dissociation (catch bond) and unfolds the GPIbα leucine-rich repeat domain (LRRD) and juxtamembrane mechanosensitive domain (MSD). How these mechanical processes trigger biochemical signals remains unknown. Here we analyze these extracellular events and the resulting intracellular Ca2+ on a single platelet in real time, revealing that LRRD unfolding intensifies the Ca2+ signal analogously whereas MSD unfolding determines the Ca2+ type digitally. The >30nm macroglycopeptide separating the two domains transmits VWF-GPIbα bond lifetime prolonged by LRRD unfolding to enhance MSD unfolding cooperatively at an optimal force, which may serve as a design principle for a generic mechanosensory machine.

Article and author information

Author details

  1. Lining Ju

    Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Yunfeng Chen

    Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Lingzhou Xue

    Department of Statistics, Pennsylvania State University, University Park, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Xiaoping Du

    Department of Pharmacology, University of Illinois at Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Cheng Zhu

    Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, United States
    For correspondence
    cheng.zhu@bme.gatech.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1718-565X

Funding

National Heart, Lung, and Blood Institute (Grant HL132019)

  • Cheng Zhu

Diabetes Australia (IRMA G179720)

  • Lining Ju

University of Sydney (2016 Sydney Medical School ECR Kickstart Grant)

  • Lining Ju

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

Reviewing Editor

  1. Taekjip Ha, Johns Hopkins University School of Medicine, United States

Ethics

Human subjects: Human RBCs and platelets for BFP experiments were collected abiding a protocol (#H12354) approved by the Institute Review Broad of Georgia Institute of Technology. Informed consent was obtained from each blood donor.

Version history

  1. Received: February 23, 2016
  2. Accepted: July 18, 2016
  3. Accepted Manuscript published: July 19, 2016 (version 1)
  4. Version of Record published: September 13, 2016 (version 2)

Copyright

© 2016, Ju 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

  • 2,512
    views
  • 572
    downloads
  • 67
    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. Lining Ju
  2. Yunfeng Chen
  3. Lingzhou Xue
  4. Xiaoping Du
  5. Cheng Zhu
(2016)
Cooperative unfolding of distinctive mechanoreceptor domains transduces force into signals
eLife 5:e15447.
https://doi.org/10.7554/eLife.15447

Share this article

https://doi.org/10.7554/eLife.15447

Categories and tags

Research organism

Further reading

    1. Structural Biology and Molecular Biophysics

    Plasticity of the proteasome-targeting signal Fat10 enhances substrate degradation

    Hitendra Negi, Aravind Ravichandran ... Ranabir Das
    Research Article

    The proteasome controls levels of most cellular proteins, and its activity is regulated under stress, quiescence, and inflammation. However, factors determining the proteasomal degradation rate remain poorly understood. Proteasome substrates are conjugated with small proteins (tags) like ubiquitin and Fat10 to target them to the proteasome. It is unclear if the structural plasticity of proteasome-targeting tags can influence substrate degradation. Fat10 is upregulated during inflammation, and its substrates undergo rapid proteasomal degradation. We report that the degradation rate of Fat10 substrates critically depends on the structural plasticity of Fat10. While the ubiquitin tag is recycled at the proteasome, Fat10 is degraded with the substrate. Our results suggest significantly lower thermodynamic stability and faster mechanical unfolding in Fat10 compared to ubiquitin. Long-range salt bridges are absent in the Fat10 structure, creating a plastic protein with partially unstructured regions suitable for proteasome engagement. Fat10 plasticity destabilizes substrates significantly and creates partially unstructured regions in the substrate to enhance degradation. NMR-relaxation-derived order parameters and temperature dependence of chemical shifts identify the Fat10-induced partially unstructured regions in the substrate, which correlated excellently to Fat10-substrate contacts, suggesting that the tag-substrate collision destabilizes the substrate. These results highlight a strong dependence of proteasomal degradation on the structural plasticity and thermodynamic properties of the proteasome-targeting tags.

    1. Biochemistry and Chemical Biology
    2. Structural Biology and Molecular Biophysics

    Special Issue: Allosteric regulation of kinase activity

    Amy H Andreotti, Volker Dötsch
    Editorial

    The articles in this special issue highlight how modern cellular, biochemical, biophysical and computational techniques are allowing deeper and more detailed studies of allosteric kinase regulation.

    1. Developmental Biology
    2. Structural Biology and Molecular Biophysics

    Structure and function of the ROR2 cysteine-rich domain in vertebrate noncanonical WNT5A signaling

    Samuel C Griffiths, Jia Tan ... Hsin-Yi Henry Ho
    Research Article Updated

    The receptor tyrosine kinase ROR2 mediates noncanonical WNT5A signaling to orchestrate tissue morphogenetic processes, and dysfunction of the pathway causes Robinow syndrome, brachydactyly B, and metastatic diseases. The domain(s) and mechanisms required for ROR2 function, however, remain unclear. We solved the crystal structure of the extracellular cysteine-rich (CRD) and Kringle (Kr) domains of ROR2 and found that, unlike other CRDs, the ROR2 CRD lacks the signature hydrophobic pocket that binds lipids/lipid-modified proteins, such as WNTs, suggesting a novel mechanism of ligand reception. Functionally, we showed that the ROR2 CRD, but not other domains, is required and minimally sufficient to promote WNT5A signaling, and Robinow mutations in the CRD and the adjacent Kr impair ROR2 secretion and function. Moreover, using function-activating and -perturbing antibodies against the Frizzled (FZ) family of WNT receptors, we demonstrate the involvement of FZ in WNT5A-ROR signaling. Thus, ROR2 acts via its CRD to potentiate the function of a receptor super-complex that includes FZ to transduce WNT5A signals.