F-Box Proteins FKF1 and LKP2 Act in Concert with ZEITLUPE to Control Arabidopsis Clock Progression
F-Box Proteins FKF1 and LKP2 Act in Concert with ZEITLUPE to Control Arabidopsis Clock Progression
复制标题
DOI：
10.1105/tpc.109.072843
复制
发表时间：
2010-03-01
期刊：
影响因子：
11.6
通讯作者：
Imaizumi, Takato
中科院分区：
文献类型：
--
作者：
Baudry, Antoine;Ito, Shogo;Imaizumi, Takato
ZTL介导的蛋白质周转调控是拟南芥生物钟的重要机制。在这里，我们报告，黄素结合，KELCH重复，F-BOX 1（FKF 1）和LOV KELCH蛋白2（LKP 2）在ZTL缺乏的昼夜节律钟中发挥类似的作用。与fkf 1中细微的生物钟缺陷相比，ztl fkf 1中的生物钟具有比ztl中长得多的周期。在ztl fkf 1 lkp 2中，几个时钟参数受到的影响甚至比ztl fkf 1更严重。尽管zt 1中的晚伸长下胚轴（LHY）和昼夜节律相关1（CCA 1）表达水平低于野生型，但将fkf 1和lkp 2突变引入zt 1突变体中显著降低了LHY表达，而不进一步影响CCA 1表达。这证明了ZTL、FKF 1和LKP 2在LHY和CCA 1表达调节中的不同贡献。此外，FKF 1和LKP 2还与CAB表达的时间安排1（T0 C1）和假反应调节因子5（PRR 5）相互作用，并且与ztl中相比，这两种蛋白在ztl fkf 1和ztl fkf 1 lkp 2中进一步稳定。我们的研究结果表明，ZTL，FKF 1和LKP 2一起调节TOC 1和PRR 5降解，是确定昼夜节律振荡周期和增强鲁棒性的主要贡献者。
Regulation of protein turnover mediated by ZEITLUPE (ZTL) constitutes an important mechanism of the circadian clock in Arabidopsis thaliana. Here, we report that FLAVIN BINDING, KELCH REPEAT, F-BOX1 (FKF1) and LOV KELCH PROTEIN2 (LKP2) play similar roles to ZTL in the circadian clock when ZTL is absent. In contrast with subtle circadian clock defects in fkf1, the clock in ztl fkf1 has a considerably longer period than in ztl. In ztl fkf1 lkp2, several clock parameters were even more severely affected than in ztl fkf1. Although LATE ELONGATED HYPOCOTYL (LHY) and CIRCADIAN CLOCK ASSOCIATED1 (CCA1) expression levels are lower in ztl than in the wild type, introducing both fkf1 and lkp2 mutations into the ztl mutant dramatically diminished LHY expression without further affecting CCA1 expression. This demonstrates different contributions of ZTL, FKF1, and LKP2 in the regulation of LHY and CCA1 expression. In addition, FKF1 and LKP2 also interacted with TIMING OF CAB EXPRESSION1 (TOC1) and PSEUDO-RESPONSE REGULATOR5 (PRR5), and both proteins were further stabilized in ztl fkf1 and ztl fkf1 lkp2 compared with in ztl. Our results indicate that ZTL, FKF1, and LKP2 together regulate TOC1 and PRR5 degradation and are major contributors to determining the period of circadian oscillation and enhancing robustness.