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bioRxiv · 10.1101/313635

Self-organization of Plk4 regulates symmetry breaking in centriole duplication.

Yamamoto, S.·Kitagawa, D.
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Abstract

During centriole duplication, a single daughter centriole is formed near the mother centriole. The mechanism that determines a single duplication site is unknown. Here, we demonstrate that intrinsic self-organization of Plk4 underlies symmetry breaking in centriole duplication. We show that in its nonphosphorylated state, Plk4 preferentially self-assembles via a disordered linker and that this self-assembly is prevented by autophosphorylation. Consistently, the dissociation dynamics of centriolar Plk4 are controlled by autophosphorylation. We further found that autophophorylated Plk4 is localized as a single focus around the mother centriole before procentriole formation, and is subsequently targeted for STIL-HsSAS6 loading. Perturbing Plk4 self-organization affects the asymmetry of centriolar Plk4 distribution and centriole duplication. We propose that the spatial patterning of Plk4 directs a single duplication site per mother centriole.

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Yamamoto, S., Kitagawa, D.. 2018-05-03. Self-organization of Plk4 regulates symmetry breaking in centriole duplication.. https://doi.org/10.1101/313635

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