SCF-bTrCP mediates the degradation of Cep68 intercentrosomal linker protein to control the disassembly of the pericentriolar material in mitosis

Pagan J1, Jones M2 and Pagano M3

  1. University of Queensland, SBMS.
  2. Memorial Sloan Kettering Cancer Center.
  3. New York University Medical Center.

Skp1-Cul1-F-box protein (SCF) complexes are the best-characterised of the multisubunit E3 Ubiquitin ligases. Each SCF complex contains one of 69 exchangeable substrate-targeting subunits, called F-box proteins. Core SCF components, SKP1 and CUL1, localise to mitotic and interphase centrosome suggesting that SCF ligases mediate the turnover of centrosomal substrates. Indeed, several specific F-box proteins have been recently shown to regulate the stability of key centrosome proteins, including PLK4 kinase (by SCF-bTrCP), the master regulator of centriole duplication. We demonstrate that SCF-bTrCP also mediates the degradation of Cep68 intercentrosomal linker protein in mitosis. Cep68 degradation is initiated by PLK1 phosphorylation of Cep68 on Ser 332, allowing recognition by bTrCP. The removal of Cep68 mediated by PLK1 and bTrCP is the first in a series of relocalization and degradation mechanisms in mitosis required to reset the centriole to a duplication competent configuration.