Molecular Analysis of the rbcS Multigene Family

转录调控是植物红细胞基因家族发育和器官特异性表达的重要调控步骤。在植物基因中，红细胞启动子是最具特征的顺式作用DNA序列元件和交易因子之一。相比之下，人们对调控成分与发育计划的整合知之甚少。使用番茄作为模型系统，我们已经证明每个红细胞启动子的时间和器官特异性活性与DNA结合蛋白与启动子区域之间共享或独特的特定DNA序列的复杂相互作用的变化相关。在番茄果实中，除了一个红细胞启动子dna -蛋白复合物外，其他所有的红细胞启动子dna -蛋白复合物在果实从幼嫩到成熟的过渡过程中消失。本研究将探讨dna -蛋白质相互作用中发育和器官特异性差异的控制机制。该项目将重点研究五种具有独特结合特性的不同dna结合蛋白。通过实验确定了这些蛋白在红细胞转录控制中的功能，并确定了这些蛋白在不同器官和果实发育过程中的表达是如何被调节的。这种方法将为植物发育过程中调控dna结合蛋白的机制提供新的重要见解。

Transcriptional regulation is an important control step in the developmental and organ-specific expression of the rbcS gene family in plants. Among plant genes, the rbcS promoter is one of the best characterized for cis-acting DNA sequence elements and transacting factors. In contrast, much less is known about the integration of the regulatory components into the developmental program. Using tomato as a model system, we have shown that the temporal and organ-specific activity of each rbcS promoter is correlated with changes in the complex interaction of DNA-binding proteins with specific DNA sequences that are shared or unique among the promoter regions. In tomato fruit, all but one of the rbcS promoter DNA-protein complexes disappear during the transition from young to ripening fruit. This proposal will investigate the mechanisms that control the developmental and organ-specific differences in DNA-protein interactions. The project will focus on five different DNA-binding proteins with unique binding characteristics. Experiments are presented to establish the function of the proteins in rbcS transcriptional control and to determine how the expression of the proteins is regulated in different organs and during fruit development. %%% This approach will provide novel and important insights into the mechanisms that control regulatory DNA-binding proteins during plant development.