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Circadian phase-specific degradation of the F-box protein ZTL is mediated by the proteasome.

ABSTRACT: Critical to the maintenance of circadian rhythmicity is the cyclic expression of at least some components of the central oscillator. High-amplitude cycling of mRNA and protein abundance, protein phosphorylation and nuclear/cytoplasmic shuttling have all been implicated in the maintenance of circadian period. Here we use a newly characterized Arabidopsis suspension cell culture to establish that the rhythmic changes in the levels of the clock-associated F-box protein, ZTL, are posttranscriptionally controlled through different circadian phase-specific degradation rates. This proteolysis is proteasome dependent, implicating ZTL itself as substrate for ubiquitination. This demonstration of circadian phase-regulated degradation of an F-box protein, which itself controls circadian period, suggests a novel regulatory feedback mechanism among known circadian systems.

SUBMITTER: Kim WY

PROVIDER: S-EPMC404699 | biostudies-literature | 2003 Apr

REPOSITORIES: biostudies-literature

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Circadian phase-specific degradation of the F-box protein ZTL is mediated by the proteasome.

Kim Woe-Yeon WY Geng Ruishuang R Somers David E DE

Proceedings of the National Academy of Sciences of the United States of America 20030328 8

Critical to the maintenance of circadian rhythmicity is the cyclic expression of at least some components of the central oscillator. High-amplitude cycling of mRNA and protein abundance, protein phosphorylation and nuclear/cytoplasmic shuttling have all been implicated in the maintenance of circadian period. Here we use a newly characterized Arabidopsis suspension cell culture to establish that the rhythmic changes in the levels of the clock-associated F-box protein, ZTL, are posttranscriptional ...[more]

PMID: 12665620

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Dataset Information

Circadian phase-specific degradation of the F-box protein ZTL is mediated by the proteasome.

Publications

Circadian phase-specific degradation of the F-box protein ZTL is mediated by the proteasome.

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