iScience (Oct 2019)

Two NEMO-like Ubiquitin-Binding Domains in CEP55 Differently Regulate Cytokinesis

  • Keïs Nabhane Said Halidi,
  • Elisabeth Fontan,
  • Alix Boucharlat,
  • Laurianne Davignon,
  • Marine Charpentier,
  • Mikaël Boullé,
  • Robert Weil,
  • Alain Israël,
  • Emmanuel Laplantine,
  • Fabrice Agou

Journal volume & issue
Vol. 20
pp. 292 – 309

Abstract

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Summary: CEP55 regulates the final critical step of cell division termed cytokinetic abscission. We report herein that CEP55 contains two NEMO-like ubiquitin-binding domains (UBDs), NOA and ZF, which regulate its function in a different manner. In vitro studies of isolated domains showed that NOA adopts a dimeric coiled-coil structure, whereas ZF is based on a UBZ scaffold. Strikingly, CEP55 knocked-down HeLa cells reconstituted with the full-length CEP55 ubiquitin-binding defective mutants, containing structure-guided mutations either in NOACEP55 or ZFCEP55 domains, display severe abscission defects. In addition, the ZFCEP55 can be functionally replaced by some ZF-based UBDs belonging to the UBZ family, indicating that the essential function of ZFCEP55 is to act as ubiquitin receptor. Our work reveals an unexpected role of CEP55 in non-degradative ubiquitin signaling during cytokinetic abscission and provides a molecular basis as to how CEP55 mutations can lead to neurological disorders such as the MARCH syndrome. : Biochemistry; Cell Biology; Structural Biology; Protein Structure Aspects Subject Areas: Biochemistry, Cell Biology, Structural Biology, Protein Structure Aspects