Scanning the Arabidopsis proteome for targets of small signaling molecules. Yeast threehybrid approach towards the identification of jasmonate receptors

多细胞生物体，无论是植物还是动物，通过使用小信号分子在细胞或器官之间进行通信来协调它们的生长和发育以及对环境的许多反应。已建立的植物激素包括生长素、细胞分裂素、赤霉素、油菜素类固醇、脱落酸(ABA)和茉莉酸(JA)，它们介导了许多生理生化反应。然而，与动物系统相比，我们对植物激素感知和信号传递的分子机制的了解仍然是零散的，尽管最近成功地识别了这些高活性化合物的受体，如生长素、细胞分裂素、赤霉素和油菜素类固醇。其他受体仍然难以捉摸或存在疑问，即JA和ABA受体。我们希望通过一种新的实验方法-酵母三杂交技术来寻找JA和ABA的主要靶点，该技术允许在体内直接功能克隆与合成杂化配体相互作用的蛋白质。利用从受到不同胁迫的几个器官、组织和植物合成的几个cDNA文库，将扫描拟南芥整个表达基因组(蛋白质组)中的JA和ABA靶标，从而提供JA和ABA结合蛋白的系统概述。值得注意的是，酵母三杂交技术应用于植物系统的发展将使人们能够系统地寻找其他有机小分子的靶标，从而有利于整个植物科学界。

Multicellular organisms, whether plant or animal, coordinate their growth and development and many responses to the environment by using small signaling molecules for communication between cells or organs. The established plant hormones include auxin, cytokinin, gibberellin, brassinosteroids, abscisic acid (ABA), and jasmonic acid (JA), which mediate numerous physiological and biochemical responses. However, in comparison to animal systems, our knowledge about the molecular mechanisms of hormone perception and signaling in plants is still fragmentary, despite the recent success of identifying receptors for several of these highly active compounds, e.g. auxin, cytokinin, gibberellin, and brassinosteroids. Other receptors remained elusive or in question, namely those for JA and ABA. We want to search for the primary targets of JA and ABA by using a new experimental approach, the yeast three-hybrid technology, which allows direct functional cloning of proteins that interact with synthetic hybrid ligands in vivo. Using several cDNA libraries synthesized from several organs, tissues, and plants that have received different kinds of stress, the whole expressed genome (proteome) of Arabidopsis thaliana will be scanned for JA and ABA targets, thereby providing a system-wide overview of JA- and ABA-binding proteins. Significantly, the development of the yeast three-hybrid technology for application to plant systems will allow the systematic search for targets of other organic small molecules and hence will be beneficial for the whole plant science community.