1. Structural Biology and Molecular Biophysics

Pore mutation N617D in the skeletal muscle DHPR blocks Ca2+ influx due to atypical high-affinity Ca2+ binding

  1. Anamika Dayal  Is a corresponding author
  2. Monica L Fernández-Quintero
  3. Klaus R Liedl
  4. Manfred Grabner  Is a corresponding author
  1. Medical University of Innsbruck, Austria
  2. University of Innsbruck, Austria
https://doi.org/10.7554/eLife.63435
Share this article
Cite this article
  1. Anamika Dayal
  2. Monica L Fernández-Quintero
  3. Klaus R Liedl
  4. Manfred Grabner
(2021)
Pore mutation N617D in the skeletal muscle DHPR blocks Ca2+ influx due to atypical high-affinity Ca2+ binding
eLife 10:e63435.
https://doi.org/10.7554/eLife.63435
  2. Download BibTeX
  3. Download .RIS

Abstract

Skeletal muscle excitation-contraction (EC) coupling roots in Ca2+-influx-independent inter-channel signaling between the sarcolemmal dihydropyridine receptor (DHPR) and the ryanodine receptor (RyR1) in the sarcoplasmic reticulum. Although DHPR Ca2+ influx is irrelevant for EC coupling, its putative role in other muscle-physiological and developmental pathways was recently examined using two distinct genetically engineered mouse models carrying Ca2+ non-conducting DHPRs: DHPR(N617D) (Dayal et al., 2017) and DHPR(E1014K) (Lee et al., 2015). Surprisingly, despite complete block of DHPR Ca2+-conductance, histological, biochemical, and physiological results obtained from these two models were contradictory. Here we characterize the permeability and selectivity properties and henceforth the mechanism of Ca2+ non-conductance of DHPR(N617). Our results reveal that only mutant DHPR(N617D) with atypical high-affinity Ca2+ pore-binding is tight for physiologically relevant monovalent cations like Na+ and K+. Consequently, we propose a molecular model of cooperativity between two ion selectivity rings formed by negatively charged residues in the DHPR pore region.

Data availability

All data generated or analyzed 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. Anamika Dayal

    Department of Genetics and Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
    For correspondence
    anamika.dayal@i-med.ac.at
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8075-8812

  2. Monica L Fernández-Quintero

    Department of Physiology and Medical Physics, University of Innsbruck, Innsbruck, Austria
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6811-6283

  3. Klaus R Liedl

    Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0985-2299

  4. Manfred Grabner

    Department of Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
    For correspondence
    manfred.grabner@i-med.ac.at
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5196-4024

Funding

Austrian Science Fund (P23229-B09)

  • Manfred Grabner

Austrian Science Fund (P27392-B21)

  • Anamika Dayal
  • Manfred Grabner

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

Copyright

© 2021, Dayal 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

  • 764
    views
  • 102
    downloads
  • 4
    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. Anamika Dayal
  2. Monica L Fernández-Quintero
  3. Klaus R Liedl
  4. Manfred Grabner
(2021)
Pore mutation N617D in the skeletal muscle DHPR blocks Ca2+ influx due to atypical high-affinity Ca2+ binding
eLife 10:e63435.
https://doi.org/10.7554/eLife.63435

Share this article

https://doi.org/10.7554/eLife.63435

Categories and tags

Research organism

Further reading

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

    Genetic code expansion, click chemistry, and light-activated PI3K reveal details of membrane protein trafficking downstream of receptor tyrosine kinases

    Duk-Su Koh, Anastasiia Stratiievska ... Sharona E Gordon
    Tools and Resources

    Ligands such as insulin, epidermal growth factor, platelet-derived growth factor, and nerve growth factor (NGF) initiate signals at the cell membrane by binding to receptor tyrosine kinases (RTKs). Along with G-protein-coupled receptors, RTKs are the main platforms for transducing extracellular signals into intracellular signals. Studying RTK signaling has been a challenge, however, due to the multiple signaling pathways to which RTKs typically are coupled, including MAP/ERK, PLCγ, and Class 1A phosphoinositide 3-kinases (PI3K). The multi-pronged RTK signaling has been a barrier to isolating the effects of any one downstream pathway. Here, we used optogenetic activation of PI3K to decouple its activation from other RTK signaling pathways. In this context, we used genetic code expansion to introduce a click chemistry noncanonical amino acid into the extracellular side of membrane proteins. Applying a cell-impermeant click chemistry fluorophore allowed us to visualize delivery of membrane proteins to the plasma membrane in real time. Using these approaches, we demonstrate that activation of PI3K, without activating other pathways downstream of RTK signaling, is sufficient to traffic the TRPV1 ion channels and insulin receptors to the plasma membrane.

    1. Structural Biology and Molecular Biophysics

    Nuclear Receptors: A new mode of inhibition

    Andrew D Huber, Taosheng Chen
    Insight

    Complementary structural biology approaches reveal how an agonist and a covalent inhibitor simultaneously bind to a nuclear receptor.

    1. Structural Biology and Molecular Biophysics

    Decoupling of the onset of anharmonicity between a protein and its surface water around 200 K

    Lirong Zheng, Bingxin Zhou ... Liang Hong
    Short Report

    The protein dynamical transition at ~200 K, where the biomolecule transforms from a harmonic, non-functional form to an anharmonic, functional state, has been thought to be slaved to the thermal activation of dynamics in its surface hydration water. Here, by selectively probing the dynamics of protein and hydration water using elastic neutron scattering and isotopic labeling, we found that the onset of anharmonicity in the two components around 200 K is decoupled. The one in protein is an intrinsic transition, whose characteristic temperature is independent of the instrumental resolution time, but varies with the biomolecular structure and the amount of hydration, while the one of water is merely a resolution effect.