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Proteomic Profiling of Microtubule Self-organization in M-phase.

ABSTRACT: Microtubules (MTs) and associated proteins can self-organize into complex structures such as the bipolar spindle, a process in which RanGTP plays a major role. Addition of RanGTP to M-phase Xenopus egg extracts promotes the nucleation and self-organization of MTs into asters and bipolar-like structures in the absence of centrosomes or chromosomes. We show here that the complex proteome of these RanGTP-induced MT assemblies is similar to that of mitotic spindles. Using proteomic profiling we show that MT self-organization in the M-phase cytoplasm involves the non-linear and non-stoichiometric recruitment of proteins from specific functional groups. Our study provides for the first time a temporal understanding of the protein dynamics driving MT self-organization in M-phase.

SUBMITTER: Rosas-Salvans M

PROVIDER: S-EPMC6166669 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Proteomic Profiling of Microtubule Self-organization in M-phase.

Rosas-Salvans Miquel M Cavazza Tommaso T Espadas Guadalupe G Sabido Eduard E Vernos Isabelle I

Molecular & cellular proteomics : MCP 20180703 10

Microtubules (MTs) and associated proteins can self-organize into complex structures such as the bipolar spindle, a process in which RanGTP plays a major role. Addition of RanGTP to M-phase <i>Xenopus</i> egg extracts promotes the nucleation and self-organization of MTs into asters and bipolar-like structures in the absence of centrosomes or chromosomes. We show here that the complex proteome of these RanGTP-induced MT assemblies is similar to that of mitotic spindles. Using proteomic profiling ...[more]

PMID: 29970457

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