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A molecular mechanism of mitotic centrosome assembly in Drosophila.

ABSTRACT: Centrosomes comprise a pair of centrioles surrounded by pericentriolar material (PCM). The PCM expands dramatically as cells enter mitosis, but it is unclear how this occurs. In this study, we show that the centriole protein Asl initiates the recruitment of DSpd-2 and Cnn to mother centrioles; both proteins then assemble into co-dependent scaffold-like structures that spread outwards from the mother centriole and recruit most, if not all, other PCM components. In the absence of either DSpd-2 or Cnn, mitotic PCM assembly is diminished; in the absence of both proteins, it appears to be abolished. We show that DSpd-2 helps incorporate Cnn into the PCM and that Cnn then helps maintain DSpd-2 within the PCM, creating a positive feedback loop that promotes robust PCM expansion around the mother centriole during mitosis. These observations suggest a surprisingly simple mechanism of mitotic PCM assembly in flies.

SUBMITTER: Conduit PT

PROVIDER: S-EPMC4175739 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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A molecular mechanism of mitotic centrosome assembly in Drosophila.

Conduit Paul T PT Richens Jennifer H JH Wainman Alan A Holder James J Vicente Catarina C CC Pratt Metta B MB Dix Carly I CI Novak Zsofia A ZA Dobbie Ian M IM Schermelleh Lothar L Raff Jordan W JW

eLife 20140822

Centrosomes comprise a pair of centrioles surrounded by pericentriolar material (PCM). The PCM expands dramatically as cells enter mitosis, but it is unclear how this occurs. In this study, we show that the centriole protein Asl initiates the recruitment of DSpd-2 and Cnn to mother centrioles; both proteins then assemble into co-dependent scaffold-like structures that spread outwards from the mother centriole and recruit most, if not all, other PCM components. In the absence of either DSpd-2 or ...[more]

PMID: 25149451

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