Molecular basis for AUXIN RESPONSE FACTOR protein interaction and the control of auxin response repression
Molecular basis for AUXIN RESPONSE FACTOR protein interaction and the control of auxin response repression
复制标题
DOI：
10.1073/pnas.1400074111
复制
发表时间：
2014-04-08
影响因子：
11.1
通讯作者：
Strader, Lucia C.
中科院分区：
文献类型：
--
作者：
Korasick, David A.;Westfall, Corey S.;Strader, Lucia C.
在植物中，生长素应答因子（AUXIN RESPONSE FACTOR， ARF）转录因子家族调控着生长素应答的基因表达。在缺乏生长素的情况下，ARF转录因子通过与生长素/吲哚3-乙酸（Aux/IAA）蛋白相互作用而受到抑制。尽管ARF和Aux/IAA蛋白的C端促进了它们的同质和异质寡聚化，但这种相互作用的分子基础仍不清楚。拟南芥ARF7 c端相互作用结构域的晶体结构揭示了Phox和Bem1p （PB1）结构域，该结构域为蛋白质定向相互作用提供正负静电界面。ARF7 PB1结构域界面残基的突变产生单体蛋白，并消除与自身和IAA17的相互作用。在拟南芥中，携带PB1突变的稳定的Aux/IAA蛋白（即IAA16）的表达表明，ARF蛋白抑制需要多聚合，从而导致生长素信号传导模型的改进。
In plants, the AUXIN RESPONSE FACTOR (ARF) transcription factor family regulates gene expression in response to auxin. In the absence of auxin, ARF transcription factors are repressed by interaction with AUXIN/INDOLE 3-ACETIC ACID (Aux/IAA) proteins. Although the C termini of ARF and Aux/IAA proteins facilitate their homo-and heterooligomerization, the molecular basis for this interaction remained undefined. The crystal structure of the C-terminal interaction domain of Arabidopsis ARF7 reveals a Phox and Bem1p (PB1) domain that provides both positive and negative electrostatic interfaces for directional protein interaction. Mutation of interface residues in the ARF7 PB1 domain yields monomeric protein and abolishes interaction with both itself and IAA17. Expression of a stabilized Aux/IAA protein (i.e., IAA16) bearing PB1 mutations in Arabidopsis suggests a multimerization requirement for ARF protein repression, leading to a refined auxin-signaling model.