1. Biochemistry and Chemical Biology
  2. Structural Biology and Molecular Biophysics
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Structural basis of nucleic-acid recognition and double-strand unwinding by the essential neuronal protein Pur-alpha

  1. Janine Weber
  2. Han Bao
  3. Christoph Hartlmüller
  4. Zhiqin Wang
  5. Almut Windhager
  6. Robert Janowski
  7. Tobias Madl
  8. Peng Jin
  9. Dierk Niessing  Is a corresponding author
  1. Helmholtz Zentrum München - German research center for environmental health, Germany
  2. Emory University, United States
  3. Technische Universität München, Germany
Research Article
  • Cited 15
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Cite this article as: eLife 2016;5:e11297 doi: 10.7554/eLife.11297

Abstract

The neuronal DNA-/RNA-binding protein Pur-alpha is a transcription regulator and core factor for mRNA-localization. Pur-alpha deficient mice die after birth with pleiotropic neuronal defects. Here we report the crystal structure of the DNA-/RNA-binding domain of Pur-alpha in complex with ssDNA. It reveals base-specific recognition and offers a molecular explanation for the effect of point mutations in the 5q31.3 microdeletion syndrome. Consistent with the crystal structure, biochemical and NMR data indicate that Pur-alpha binds DNA and RNA in the same way, suggesting binding modes for tri- and hexanucleotide repeat RNAs in two neurodegenerative RNAopathies. Additionally, structure-based in vitro experiments resolved the molecular mechanism of Pur-alpha's unwindase activity. Complementing in vivo analyses in Drosophila demonstrated the importance of a highly conserved phenylalanine for Pur-alpha's unwinding and neuroprotective function. By uncovering the molecular mechanisms of nucleic-acid binding, this study contributes to understanding the cellular role of Pur-alpha and its implications in neurodegenerative diseases.

Article and author information

Author details

  1. Janine Weber

    Institute of Structural Biology, Helmholtz Zentrum München - German research center for environmental health, Neuherberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Han Bao

    Department of Human Genetics, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Christoph Hartlmüller

    Center for Integrated Protein Science Munich, Department of Chemistry, Technische Universität München, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Zhiqin Wang

    Department of Human Genetics, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Almut Windhager

    Institute of Structural Biology, Helmholtz Zentrum München - German research center for environmental health, Neuherberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Robert Janowski

    Institute of Structural Biology, Helmholtz Zentrum München - German research center for environmental health, Neuherberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Tobias Madl

    Institute of Structural Biology, Helmholtz Zentrum München - German research center for environmental health, Neuherberg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Peng Jin

    Department of Human Genetics, Emory University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Dierk Niessing

    Institute of Structural Biology, Helmholtz Zentrum München - German research center for environmental health, Neuherberg, Germany
    For correspondence
    dierk.niessing@med.uni-muenchen.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Karsten Weis, ETH Zürich, Switzerland

Publication history

  1. Received: September 3, 2015
  2. Accepted: January 7, 2016
  3. Accepted Manuscript published: January 8, 2016 (version 1)
  4. Accepted Manuscript updated: January 12, 2016 (version 2)
  5. Version of Record published: February 11, 2016 (version 3)

Copyright

© 2016, Weber 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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