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

• DOI: 10.1073/pnas.0736949100
• Publication Date: 2003-04-15T22:56:03Z
• Authors: Woe-Yeon Kim; Ruishuang Geng; David E. Somers
• Keywords: Protein Degradation; Proteolysis; Protein turnover; F-box protein

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