Department of Biochemistry, Okayama University of Science, Okayama, 700-0005 Japan.
Plant Cell Physiol. 2012 Jun;53(6):965-75. doi: 10.1093/pcp/pcs035. Epub 2012 Mar 19.
IAA, a naturally occurring auxin, is a simple signaling molecule that regulates many diverse steps of plant development. Auxin essentially coordinates plant development through transcriptional regulation. Auxin binds to TIR1/AFB nuclear receptors, which are F-box subunits of the SCF ubiquitin ligase complex. The auxin signal is then modulated by the quantitative and qualitative responses of the Aux/IAA repressors and the auxin response factor (ARF) transcription factors. The specificity of the auxin-regulated gene expression profile is defined by several factors, such as the expression of these regulatory proteins, their post-transcriptional regulation, their stability and the affinity between these regulatory proteins. Auxin-binding protein 1 (ABP1) is a candidate protein for an auxin receptor that is implicated in non-transcriptional auxin signaling. ABP1 also affects TIR1/AFB-mediated auxin-responsive gene expression, implying that both the ABP1 and TIR1/AFB signaling machineries coordinately control auxin-mediated physiological events. Systematic approaches using the comprehensive mapping of the expression and interaction of signaling modules and computational modeling would be valuable for integrating our knowledge of auxin signals and responses.
IAA 是一种天然存在的生长素，是一种简单的信号分子，调节植物发育的许多不同步骤。生长素通过转录调控基本上协调植物的发育。生长素与 TIR1/AFB 核受体结合，TIR1/AFB 核受体是 SCF 泛素连接酶复合物的 F 框亚基。然后，生长素信号通过Aux/IAA 阻遏物和生长素反应因子 (ARF) 转录因子的定量和定性反应进行调节。生长素调节的基因表达谱的特异性由几个因素定义，例如这些调节蛋白的表达、它们的转录后调节、它们的稳定性以及这些调节蛋白之间的亲和力。生长素结合蛋白 1 (ABP1) 是一种涉及非转录生长素信号传导的生长素受体的候选蛋白。ABP1 还影响 TIR1/AFB 介导的生长素应答基因表达，这意味着 ABP1 和 TIR1/AFB 信号机制协同控制生长素介导的生理事件。使用信号模块的表达和相互作用的综合映射以及计算建模的系统方法，对于整合我们对生长素信号和反应的知识将是有价值的。
