Simonini Sara, Stephenson Pauline, Østergaard Lars
Crop Genetics Department, John Innes Centre, Norwich NR4 7UH, UK.
Crop Genetics Department, John Innes Centre, Norwich NR4 7UH, UK
Development. 2018 Mar 1;145(5):dev158105. doi: 10.1242/dev.158105.
Organ formation in multicellular organisms depends on the coordinated activities of regulatory components that integrate developmental and hormonal cues to control gene expression and mediate cell-type specification. For example, development of the gynoecium is tightly controlled by distribution and synthesis of the plant hormone auxin. The functions of several transcription factors (TFs) have been linked with auxin dynamics during gynoecium development; yet how their activities are coordinated is not known. Here, we show that five such TFs function together to ensure polarity establishment at the gynoecium apex. The auxin response factor ETTIN (ARF3; herein, ETT) is a central component of this framework. Interaction of ETT with TF partners is sensitive to the presence of auxin and our results suggest that ETT forms part of a repressive gene-regulatory complex. We show that this function is conserved between members of the family and that variation in an ETT subdomain affects interaction strengths and gynoecium morphology. These results suggest that variation in affinities between conserved TFs can lead to morphological differences and thus contribute to the evolution of diverse organ shapes.
多细胞生物中的器官形成依赖于调控组件的协同活动，这些组件整合发育和激素信号以控制基因表达并介导细胞类型特化。例如，雌蕊的发育受到植物激素生长素分布和合成的严格控制。几种转录因子（TFs）的功能与雌蕊发育过程中的生长素动态相关；然而，它们的活动如何协调尚不清楚。在这里，我们表明五个这样的转录因子共同发挥作用，以确保雌蕊顶端的极性建立。生长素响应因子ETTIN（ARF3；本文中简称ETT）是这个框架的核心组成部分。ETT与TF伙伴的相互作用对生长素的存在敏感，我们的结果表明ETT是一个抑制性基因调控复合体的一部分。我们表明，这种功能在该家族成员之间是保守的，并且ETT一个亚结构域的变异会影响相互作用强度和雌蕊形态。这些结果表明，保守转录因子之间亲和力的变化可导致形态差异，从而有助于不同器官形状的进化。
