Regulation of signaling directionality revealed by 3D snapshots of a kinase:regulator complex in action

  1. Felipe Trajtenberg
  2. Juan A Imelio
  3. Matías R Machado
  4. Nicole Larrieux
  5. Marcelo A Marti
  6. Gonzalo Obal
  7. Ariel E Mechaly
  8. Alejandro Buschiazzo  Is a corresponding author
  1. Institut Pasteur de Montevideo, Uruguay
  2. Universidad de Buenos Aires, Argentina

Abstract

Two-component systems (TCS) are protein machineries that enable cells to respond to input signals. Histidine kinases (HK) are the sensory component, transferring information toward downstream response regulators (RR). HKs transfer phosphoryl groups to their specific RRs, but also dephosphorylate them, overall ensuring proper signaling. The mechanisms by which HKs discriminate between such disparate directions, are yet unknown. We now disclose crystal structures of the HK:RR complex DesK:DesR from Bacillus subtilis, comprising snapshots of the phosphotransfer and the dephosphorylation reactions. The HK dictates the reactional outcome through conformational rearrangements that include the reactive histidine. The phosphotransfer center is asymmetric, poised for dissociative nucleophilic substitution. The structural bases of HK phosphatase/phosphotransferase control are uncovered, and the unexpected discovery of a dissociative reactional center, sheds light on the evolution of TCS phosphotransfer reversibility. Our findings should be applicable to a broad range of signaling systems and instrumental in synthetic TCS rewiring.

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Author details

  1. Felipe Trajtenberg

    Laboratory of Molecular and Structural Microbiology, Institut Pasteur de Montevideo, Montevideo, Uruguay
    Competing interests
    The authors declare that no competing interests exist.
  2. Juan A Imelio

    Laboratory of Molecular and Structural Microbiology, Institut Pasteur de Montevideo, Montevideo, Uruguay
    Competing interests
    The authors declare that no competing interests exist.
  3. Matías R Machado

    Biomolecular Simulations, Institut Pasteur de Montevideo, Montevideo, Uruguay
    Competing interests
    The authors declare that no competing interests exist.
  4. Nicole Larrieux

    Laboratory of Molecular and Structural Microbiology, Institut Pasteur de Montevideo, Montevideo, Uruguay
    Competing interests
    The authors declare that no competing interests exist.
  5. Marcelo A Marti

    Dto. Química Biológica e IQUIBICEN-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
    Competing interests
    The authors declare that no competing interests exist.
  6. Gonzalo Obal

    Protein Biophysics Unit, Institut Pasteur de Montevideo, Montevideo, Uruguay
    Competing interests
    The authors declare that no competing interests exist.
  7. Ariel E Mechaly

    Laboratory of Molecular and Structural Microbiology, Institut Pasteur de Montevideo, Montevideo, Uruguay
    Competing interests
    The authors declare that no competing interests exist.
  8. Alejandro Buschiazzo

    Laboratory of Molecular and Structural Microbiology, Institut Pasteur de Montevideo, Montevideo, Uruguay
    For correspondence
    alebus@pasteur.edu.uy
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2509-6526

Funding

Agencia Nacional de Investigación e Innovación (FCE2009_1_2679)

  • Felipe Trajtenberg
  • Alejandro Buschiazzo

Agence Nationale de la Recherche (PCV06_138918)

  • Alejandro Buschiazzo

FOCEM (COF 03/11)

  • Alejandro Buschiazzo

Centro de Biologia Estructural del Mercosur

  • Alejandro Buschiazzo

Agencia Nacional de Investigación e Innovación (FCE2007_219)

  • Felipe Trajtenberg
  • Alejandro Buschiazzo

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

Reviewing Editor

  1. Michael Laub, Massachusetts Institute of Technology, United States

Version history

  1. Received: September 11, 2016
  2. Accepted: December 9, 2016
  3. Accepted Manuscript published: December 12, 2016 (version 1)
  4. Version of Record published: January 12, 2017 (version 2)
  5. Version of Record updated: September 5, 2017 (version 3)

Copyright

© 2016, Trajtenberg 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.

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  1. Felipe Trajtenberg
  2. Juan A Imelio
  3. Matías R Machado
  4. Nicole Larrieux
  5. Marcelo A Marti
  6. Gonzalo Obal
  7. Ariel E Mechaly
  8. Alejandro Buschiazzo
(2016)
Regulation of signaling directionality revealed by 3D snapshots of a kinase:regulator complex in action
eLife 5:e21422.
https://doi.org/10.7554/eLife.21422

Share this article

https://doi.org/10.7554/eLife.21422

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