1. Biochemistry and Chemical Biology
  2. Cell Biology

Spectrin binding motifs regulate Scribble cortical dynamics and polarity function

  1. Batiste Boëda
  2. Sandrine Etienne-Manneville  Is a corresponding author
  1. Institut Pasteur-CNRS, France
https://doi.org/10.7554/eLife.04726
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  1. Batiste Boëda
  2. Sandrine Etienne-Manneville
(2015)
Spectrin binding motifs regulate Scribble cortical dynamics and polarity function
eLife 4:e04726.
https://doi.org/10.7554/eLife.04726
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Abstract

The tumor suppressor protein Scribble (SCRIB) plays an evolutionary conserved role in cell polarity. Despite being central for its function, the molecular basis of SCRIB recruitment and stabilization at the cell cortex is poorly understood. Here we show that SCRIB binds directly to the CH1 domain of β spectrins, a molecular scaffold that contributes to the cortical actin cytoskeleton and connects it to the plasma membrane. We have identified a short evolutionary conserved peptide motif named SADH motif(SCRIB ABLIMs DMTN Homology) which is necessary and sufficient to mediate protein interaction with β spectrins. The SADH domains contribute to SCRIB dynamics at the cell cortex and SCRIB polarity function. Furthermore, mutations in SCRIB SADH domains associated with spina bifida and cancer impact the stability of SCRIB at the plasma membrane, suggesting that SADH domain alterations may participate in human pathology.

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Author details

  1. Batiste Boëda

    Cell Polarity, Migration and Cancer Unit, Institut Pasteur-CNRS, Paris, France
    Competing interests
    The authors declare that no competing interests exist.

  2. Sandrine Etienne-Manneville

    Cell Polarity, Migration and Cancer Unit, Institut Pasteur-CNRS, Paris, France
    For correspondence
    setienne@pasteur.fr
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Boëda & Etienne-Manneville

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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