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Sticking together the Crumbs — an unexpected function for an old friend

Nature Reviews Molecular Cell Biology volume 14, pages 307–314 (2013)Cite this article

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Abstract

Cell polarity and cell–cell junctions have pivotal roles in organizing cells into tissues and in mediating cell–cell communication. The transmembrane protein Crumbs has a well-established role in the maintenance of epithelial polarity, and it can also regulate signalling via the Notch and Hippo pathways to influence tissue growth. The functions of Crumbs in epithelial polarity and Hippo-mediated growth depend on its short intracellular domain. Recent evidence now points to a conserved and fundamental role for the extracellular domain of Crumbs in mediating homophilic Crumbs–Crumbs interactions at cell–cell junctions.

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Figure 1: Classic functions of Crumbs.
Figure 2: Role of the extracellular domain of Crumbs in the retina.
Figure 3: Crumbs–Crumbs interactions in trans mediate cell–cell communication.
Figure 4: Role of the Crumbs extracellular domain during salivary gland morphogenesis and in follicle and border cells.

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Acknowledgements

The authors apologize to colleagues whose work could not be cited or discussed in sufficient depth owing to space limitations. B.J.T. is supported by Cancer Research UK (CRUK), F.P. is supported by the Medical Research Council (MRC), and K.R. is also supported by the MRC (file reference number U105178780).

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Authors and Affiliations

  1. Barry J. Thompson is at Cancer Research UK, London Research Institute, 44 Lincolns Inn Fields, London, WC2A 3LY, UK.,

    Barry J. Thompson

  2. Franck Pichaud is at MRC Laboratory of Molecular and Cellular Biology, University College London, Gower Street, London, WC1E 6BT, UK.,

    Franck Pichaud

  3. Katja Röper is at MRC-Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge, CB2 0QH, UK.,

    Katja Röper

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Correspondence to Barry J. Thompson, Franck Pichaud or Katja Röper.

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Thompson, B., Pichaud, F. & Röper, K. Sticking together the Crumbs — an unexpected function for an old friend. Nat Rev Mol Cell Biol 14, 307–314 (2013). https://doi.org/10.1038/nrm3568

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