AtCAND1, a HEAT-repeat protein that participates in auxin signaling in arabidopsis
AtCAND1, a HEAT-repeat protein that participates in auxin signaling in arabidopsis
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DOI：
10.1104/pp.104.044495
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发表时间：
2004-06-01
期刊：
影响因子：
7.4
通讯作者：
Zhao, Y
中科院分区：
文献类型：
--
作者：
Cheng, YF;Dai, XH;Zhao, Y
生长素影响植物生长发育的许多方面。我们之前使用化学遗传学来解剖生长素信号传导机制，并鉴定出一种小分子sirtinol，它组成性地激活生长素信号传导（Y. Zhao et . [2003], Science 301: 1107-1110）。在这里，我们描述了拟南芥突变体Atcand1-1的分离、表征和克隆，该突变体是从对sirtinol不敏感的突变体的遗传筛选中出现的。AtCAND1的功能缺失突变体对sirtinol和生长素有抗性，但对赤霉素和油菜素内酯没有抗性。Atcand1表现出与axr1相似的发育表型，即叶柄短，叶片向下卷曲，花序短，育性降低。AtCAND1与人类的CAND1是同源的，后者是一种几乎完全由HEAT-repeat单元组成的蛋白质，与调节SCF蛋白降解机制的组装和拆卸有关。结合之前的生化研究，这项工作有助于阐明AtCAND1在蛋白质降解和生长素信号传导中的作用。
Auxin affects many aspects of plant growth and development. We previously used chemical genetics to dissect auxin-signaling mechanisms and identified a small molecule, sirtinol, that constitutively activated auxin signaling (Y. Zhao et al. [2003], Science 301: 1107-1110). Here we describe the isolation, characterization, and cloning of an Arabidopsis mutant Atcand1-1 that emerged from a genetic screen for mutants insensitive to sirtinol. Loss-of-function mutants of AtCAND1 were resistant to sirtinol and auxin, but not to gibberellins or brassinolide. Atcand1 displayed developmental phenotypes similar to those of axr1, namely, short petioles, downwardly curling leaves, short inflorescence, and reduced fertility. AtCAND1 is homologous to human CAND1, a protein that is composed almost entirely of HEAT-repeat units and has been implicated in regulating the assembly and disassembly of the SCF protein degradation machinery. Taken together with previous biochemical studies, this work helps to elucidate the roles of AtCAND1 in protein degradation and auxin signaling.