Structural determinants of nuclear export signal orientation in binding CRM1

  1. Ho Yee Joyce Fung
  2. Szu-chin Fu
  3. Chad A Brautigam
  4. Yuh Min Chook  Is a corresponding author
  1. University of Texas Southwestern Medical Center, United States

Abstract

The Chromosome Region of Maintenance 1 (CRM1) protein mediates nuclear export of hundreds of proteins through recognition of their nuclear export signals (NESs), which are highly variable in sequence and structure. The plasticity of the CRM1-NES interaction is not well understood, as there are many NES sequences that seem incompatible with structures of the NES-bound CRM1 groove. Crystal structures of CRM1 bound to two different NESs with unusual sequences showed the NES peptides binding the CRM1 groove in the opposite orientation (minus) to that of previously studied NESs (plus). Comparison of minus and plus NESs identified structural and sequence determinants for NES orientation. The binding of NESs to CRM1 in both orientations results in a large expansion in NES consensus patterns and therefore a corresponding expansion of potential NESs in the proteome.

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Author details

  1. Ho Yee Joyce Fung

    Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Szu-chin Fu

    Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Chad A Brautigam

    Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Yuh Min Chook

    Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, United States
    For correspondence
    yuhmin.chook@utsouthwestern.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Fung 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. Ho Yee Joyce Fung
  2. Szu-chin Fu
  3. Chad A Brautigam
  4. Yuh Min Chook
(2015)
Structural determinants of nuclear export signal orientation in binding CRM1
eLife 4:e10034.
https://doi.org/10.7554/eLife.10034

Share this article

https://doi.org/10.7554/eLife.10034

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