1. Structural Biology and Molecular Biophysics
  2. Microbiology and Infectious Disease
Download icon

Drastic changes in conformational dynamics of the antiterminator M2-1 regulate transcription efficiency in Pneumovirinae

  1. Cedric Leyrat
  2. Max Renner
  3. Karl Harlos
  4. Juha T Huiskonen
  5. Jonathan M Grimes  Is a corresponding author
  1. Wellcome Trust Centre for Human Genetics, United Kingdom
Research Article
  • Cited 26
  • Views 1,593
  • Annotations
Cite this article as: eLife 2014;3:e02674 doi: 10.7554/eLife.02674

Abstract

The M2-1 protein of human metapneumovirus (HMPV) is a zinc-binding transcription antiterminator which is highly conserved among pneumoviruses. We report the structure of tetrameric HMPV M2-1. Each protomer features a N-terminal zinc finger domain and an α-helical tetramerization motif forming a rigid unit, followed by a flexible linker and an α-helical core domain. The tetramer is asymmetric, three of the protomers exhibiting a closed conformation, and one an open conformation. Molecular dynamics simulations and SAXS demonstrate a dynamic equilibrium between open and closed conformations in solution. Structures of adenosine monophosphate- and DNA- bound M2-1 establish the role of the zinc finger domain in base-specific recognition of RNA. Binding to 'gene end' RNA sequences stabilized the closed conformation of M2-1 leading to a drastic shift in the conformational landscape of M2-1. We propose a model for recognition of gene end signals and discuss the implications of these findings for transcriptional regulation in pneumoviruses.

Article and author information

Author details

  1. Cedric Leyrat

    Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Max Renner

    Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Karl Harlos

    Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Juha T Huiskonen

    Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Jonathan M Grimes

    Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
    For correspondence
    jonathan@strubi.ox.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Volker Dötsch, Goethe University, Germany

Publication history

  1. Received: February 28, 2014
  2. Accepted: May 15, 2014
  3. Accepted Manuscript published: May 19, 2014 (version 1)
  4. Version of Record published: June 10, 2014 (version 2)

Copyright

© 2014, Leyrat 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

  • 1,593
    Page views
  • 159
    Downloads
  • 26
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, Scopus, PubMed Central.

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)

Download citations (links to download the citations from this article in formats compatible with various reference manager tools)

Open citations (links to open the citations from this article in various online reference manager services)

Further reading

    1. Computational and Systems Biology
    2. Structural Biology and Molecular Biophysics
    Xiakun Chu et al.
    Research Article

    The way in which multidomain proteins fold has been a puzzling question for decades. Until now, the mechanisms and functions of domain interactions involved in multidomain protein folding have been obscure. Here, we develop structure-based models to investigate the folding and DNA-binding processes of the multidomain Y-family DNA polymerase IV (DPO4). We uncover shifts in folding mechanism among ordered domain-wise folding, backtracking folding, and cooperative folding, modulated by interdomain interactions. These lead to "U-shaped' folding kinetics. We characterize the effects of interdomain flexibility on the promotion of DPO4-DNA (un)binding, which probably contributes to the ability of DPO4 to bypass DNA lesions, a known biological role of Y-family polymerases. We suggest that the native topology of DPO4 leads to a trade-off between fast, stable folding and tight functional DNA binding. Our approach provides an effective way to quantitatively correlate the roles of protein interactions in conformational dynamics at the multidomain level.

    1. Cell Biology
    2. Structural Biology and Molecular Biophysics
    Lukas Ded et al.
    Research Article

    Out of millions of ejaculated sperm, only a few reach the fertilization site in mammals. Flagellar Ca2+ signaling nanodomains, organized by multi-subunit CatSper calcium channel complexes, are pivotal for sperm migration in the female tract, implicating CatSper-dependent mechanisms in sperm selection. Here, using biochemical and pharmacological studies, we demonstrate that CatSper1 is an O-linked glycosylated protein, undergoing capacitation-induced processing dependent on Ca2+ and phosphorylation cascades. CatSper1 processing correlates with protein tyrosine phosphorylation (pY) development in sperm cells capacitated in vitro and in vivo. Using 3D in situ molecular imaging and ANN-based automatic detection of sperm distributed along the cleared female tract, we demonstrate that all spermatozoa past the UTJ possess intact CatSper1 signals. Together, we reveal that fertilizing mouse spermatozoa in situ are characterized by intact CatSper channel, lack of pY, and reacted acrosomes. These findings provide molecular insight into sperm selection for successful fertilization in the female reproductive tract.