n nnnRegulation of protein turnover mediated by ZEITLUPE (ZTL) constitutesan important mechanism of the circadian clock in Arabidopsisthaliana. Here, we report that FLAVIN BINDING, KELCH REPEAT,F-BOX1 (FKF1) and LOV KELCH PROTEIN2 (LKP2) play similar rolesto ZTL in the circadian clock when ZTL is absent. In contrastwith subtle circadian clock defects in fkf1, the clock in ztlfkf1 has a considerably longer period than in ztl. In ztl fkf1lkp2, several clock parameters were even more severely affectedthan in ztl fkf1. Although LATE ELONGATED HYPOCOTYL (LHY) andCIRCADIAN CLOCK ASSOCIATED1 (CCA1) expression levels are lowerin ztl than in the wild type, introducing both fkf1 and lkp2mutations into the ztl mutant dramatically diminished LHY expressionwithout further affecting CCA1 expression. This demonstratesdifferent contributions of ZTL, FKF1, and LKP2 in the regulationof LHY and CCA1 expression. In addition, FKF1 and LKP2 alsointeracted with TIMING OF CAB EXPRESSION1 (TOC1) and PSEUDO-RESPONSEREGULATOR5 (PRR5), and both proteins were further stabilizedin ztl fkf1 and ztl fkf1 lkp2 compared with in ztl. Our resultsindicate that ZTL, FKF1, and LKP2 together regulate TOC1 andPRR5 degradation and are major contributors to determining theperiod of circadian oscillation and enhancing robustness.展开▼
机译：ABSTRACTn n
n TOP n <字体颜色= 464c53>抽象 n 介绍 n 结果 n 讨论 n 方法 n 参考文献 n n nnn ZEITLUPE（ZTL）介导的蛋白质周转调节构成 拟南芥 拟南芥的生物钟的重要机制。在这里，我们报道当ZTL为ZTL时，生物钟中的FLAVIN BINDING，KELCH REPEAT， F-BOX1（FKF1）和LOV KELCH PROTEIN2（LKP2）与ZTL的作用相似。缺席。与 fkf1 中的细微的昼夜节律缺陷相比， ztl fkf1 中的时钟周期要长得多。 ztl 。在 ztl fkf1 lkp2 中，与 ztl fkf1 相比，几个时钟参数受 的影响甚至更大。尽管晚期加长的hypocotyl （ LHY ）和 CIRCADIAN CLOCK ASSOCIATED1 （ CCA1 ）表达 ztl 中的 水平低于野生型，同时引入了 fkf1 和 lkp2 ztl 突变体的>突变会大大减少 LHY 表达 ，而不会进一步影响 CCA1 的表达。这表明ZTL，FKF1和LKP2的 在 LHY 和 CCA1 表达的调节 中的不同贡献。此外，FKF1和LKP2还 与CAB EXPRESSION1（TOC1）和PSEUDO-RESPONSE REGULATOR5（PRR5）的时序相互作用，并且两种蛋白都进一步稳定化 ztl 中的 ztl fkf1 和 ztl fkf1 lkp2 中的SUP相比。我们的结果 表明ZTL，FKF1和LKP2共同调节TOC1和 PRR5降解，并且是确定 周期昼夜振荡和增强的主要因素健壮性。展开▼
