The Arabidopsis F-box protein TIR1 is an auxin receptor
The Arabidopsis F-box protein TIR1 is an auxin receptor
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DOI：
10.1038/nature03542
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发表时间：
2005-05-26
期刊：
影响因子：
64.8
通讯作者：
Leyser, O
中科院分区：
文献类型：
--
作者：
Kepinski, S;Leyser, O
尽管100年来的证据表明吲哚-3-乙酸(IAA或生长素)在植物发育中起着关键作用，但生长素的感知机制仍然难以捉摸。生长素反应的中心是基因表达的变化，这是由生长素诱导的AUX/IAA转录抑制蛋白与泛素连接酶复合体SCFTIR1之间的相互作用所引起的，从而针对它们的蛋白降解。调控的SCF介导的蛋白质降解是一种广泛存在的信号转导机制。靶向特异性由SCF的F-box蛋白亚基(在AUX/IAAs的情况下为TIR1)决定，到目前为止所有的真核基因组中都有多个F-box蛋白基因。虽然SCF-靶点相互作用通常受信号诱导的靶点修饰的调节，但我们先前已经证明，生长素信号涉及SCFTIR1的修饰。在这里，我们表明，这种修饰涉及生长素与TIR1的直接结合，因此TIR1是一种生长素受体，介导对生长素的转录反应。
Despite 100 years of evidence showing a pivotal role for indole-3-acetic acid (IAA or auxin) in plant development, the mechanism of auxin perception has remained elusive. Central to auxin response are changes in gene expression, brought about by auxin-induced interaction between the Aux/IAA transcriptional repressor proteins and the ubiquitin - ligase complex SCFTIR1, thus targeting for them proteolysis. Regulated SCF-mediated protein degradation is a widely occurring signal transduction mechanism. Target specificity is conferred by the F-box protein subunit of the SCF (TIR1 in the case of Aux/IAAs) and there are multiple F-box protein genes in all eukaryotic genomes examined so far. Although SCF - target interaction is usually regulated by signal-induced modification of the target, we have previously shown that auxin signalling involves the modification of SCFTIR1. Here we show that this modification involves the direct binding of auxin to TIR1 and thus that TIR1 is an auxin receptor mediating transcriptional responses to auxin.