Coupling morphogenesis to mitotic entry.

Krisada Sakchaisri; Satoshi Asano; Li-Rong Yu; Mark J Shulewitz; Chong J Park; Jung-Eun Park; Young-Wook Cho; Timothy D Veenstra; Jeremy Thorner; Kyung S Lee

doi:10.1073/pnas.0400641101

PubMed · 15037762

Coupling morphogenesis to mitotic entry.

Krisada Sakchaisri·Satoshi Asano·Li-Rong Yu·Mark J Shulewitz·Chong J Park·Jung-Eun Park·Young-Wook Cho·Timothy D Veenstra·Jeremy Thorner·Kyung S Lee

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Abstract

In eukaryotes, cyclin B-bound cyclin-dependent protein kinase 1 promotes mitotic entry but is held in check, in part, by Wee1 protein kinase. Timely mitotic entry in budding yeast requires inactivation of Swe1 (Wee1 ortholog). Perturbations of the septin collar at the bud neck lead to Swe1 stabilization, delaying the G(2)/M transition. Swe1 is recruited to the neck and hyperphosphorylated before ubiquitin-mediated degradation. Hsl1 kinase (Nim1 ortholog), a negative regulator of Wee1, is required for efficient Swe1 localization at the neck but seems not to phosphorylate Swe1. Here, we show that two other kinases targeted sequentially to the neck, Cla4/PAK and Cdc5/Polo, are responsible for stepwise phosphorylation and down-regulation of Swe1. This mechanism links assembly of a cellular structure to passage into mitosis.

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Cell Cycle Proteins Mitosis Morphogenesis Phosphorylation Protein Kinases Protein Serine-Threonine Kinases Protein-Tyrosine Kinases Saccharomyces cerevisiae Saccharomyces cerevisiae Proteins Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Krisada Sakchaisri, Satoshi Asano, Li-Rong Yu, Mark J Shulewitz, Chong J Park, Jung-Eun Park, Young-Wook Cho, Timothy D Veenstra, Jeremy Thorner, Kyung S Lee. 2004-03-22. Coupling morphogenesis to mitotic entry.. https://doi.org/10.1073/pnas.0400641101

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