Auxin in transcription factor complex controls polarity in plant organogenesis

转录因子复合物中的生长素控制植物器官发生中的极性

基本信息

批准号：
BB/M004112/1
负责人：
Lars Ostergaard
金额：
$ 68.36万
依托单位：
John Innes Centre
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2015
资助国家：
英国
起止时间：
2015 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FM004112%2F1
关键词：
Auxin transcription factor complex controls

项目摘要

Multicellular organisms including plants and animals develop specialised organs, which are composed of different types of tissues. The structure - or pattern - of organs is determined by the polarity within tissues along axes of symmetry. In order to coordinate polarity across a tissue or organ, multicellular organisms use mobile substances such as hormones. The plant hormone auxin was one of the first hormones ever to be studied and the effect of auxin on light-regulated plant growth (phototropism) was investigated by Charles Darwin and his son Francis in the 1880s. It was, however, not until the 1930s that the auxin molecule was isolated and its molecular structure determined as indole 3-acetic acid (IAA). In plants, auxin plays an essential role in initiating organ formation and in patterning the organs in specific tissue types, including for example lateral roots, young leaves and those of the female reproductive organ, the gynoecium. Control of auxin dynamics is achieved at the levels of biosynthesis, transport and signalling. The auxin molecule was previously shown to mediate the interactions between specific proteins thereby causing the degradation of repressors of gene expression. It has also been established that auxin can influence its own transport via inhibiting internalisation of PIN auxin transporters. Although these mechanisms of auxin signalling can explain many processes of auxin action, other transcriptional signalling pathways are likely to exist to account for the plethora of processes in which auxin plays a role. We have identified an interaction between two proteins found in the model plant Arabidopsis, which both are key regulators of polarity in the gynoecium of the flower. They have been named ETTIN and IND and both act as transcription factors (i.e. directly control the expression of genes). From experiments carried out in yeast we know that together these proteins can physically bind auxin in a so-called receptor complex, and our preliminary data suggest that the target gene set of ETT and IND changes when they bind auxin. This suggests the existence of an alternative signalling pathway for auxin. ETTIN controls the initiation and patterning of other plant organs, and in accordance with this, we identified other transcription factors that ETT can interact with in a similar auxin-sensitive manner. It is therefore likely that this new pathway is conserved in plant development. Through experiments described in this proposal, we aim to reach a mechanistic and developmental understanding of this newly discovered auxin-signalling module, which may be particularly well suited to facilitate precise switches in polarity throughout plant development.

包括植物和动物在内的多细胞生物发育出由不同类型的组织组成的专门器官。器官的结构或模式由组织内沿对称轴的极性决定。为了协调组织或器官的极性，多细胞生物使用移动物质，例如激素。植物激素生长素是最早被研究的激素之一，查尔斯·达尔文和他的儿子弗朗西斯在 1880 年代研究了生长素对光调节植物生长（向光性）的影响。然而，直到20世纪30年代，生长素分子才被分离出来，其分子结构被确定为吲哚3-乙酸（IAA）。在植物中，生长素在启动器官形成和特定组织类型中器官的形成中发挥重要作用，包括例如侧根、幼叶和雌性生殖器官雌蕊。生长素动力学的控制是在生物合成、运输和信号传导水平上实现的。先前显示生长素分子介导特定蛋白质之间的相互作用，从而导致基因表达阻遏物的降解。还已经证实，生长素可以通过抑制 PIN 生长素转运蛋白的内化来影响其自身的转运。尽管生长素信号传导的这些机制可以解释生长素作用的许多过程，但可能存在其他转录信号传导途径来解释生长素发挥作用的众多过程。我们已经确定了在模式植物拟南芥中发现的两种蛋白质之间的相互作用，这两种蛋白质都是花雌蕊极性的关键调节因子。它们被命名为 ETTIN 和 IND，均充当转录因子（即直接控制基因的表达）。通过在酵母中进行的实验，我们知道这些蛋白质可以在所谓的受体复合物中物理结合生长素，并且我们的初步数据表明，ETT 和 IND 的目标基因集在它们结合生长素时发生变化。这表明生长素存在替代信号通路。 ETTIN 控制其他植物器官的启动和模式，据此，我们确定了 ETT 可以以类似的生长素敏感方式相互作用的其他转录因子。因此，这条新途径很可能在植物发育过程中得到保留。通过本提案中描述的实验，我们的目标是对这种新发现的生长素信号模块达成机械和发育的理解，该模块可能特别适合促进整个植物发育过程中极性的精确切换。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Fruit shape diversity in the Brassicaceae is generated by varying patterns of anisotropy.

DOI：
10.1242/dev.135327
发表时间：
2016-09-15
期刊：
Development (Cambridge, England)
影响因子：
0
作者：
Eldridge T;Łangowski Ł;Stacey N;Jantzen F;Moubayidin L;Sicard A;Southam P;Kennaway R;Lenhard M;Coen ES;Østergaard L
通讯作者：
Østergaard L

Coordination of biradial-to-radial symmetry and tissue polarity by HD-ZIP II proteins.