Control of Cell Specification and Gene Expression in Anther Development

开花植物的雄性生殖过程发生在花药中。这个器官由几种特殊的组织和细胞类型组成，负责产生含有精子细胞的花粉粒。花药组织由花分生组织内存在的细胞谱系以有序的模式形成。这些组织与出现在发育中的花药原基中特定位置或区域的前体细胞不同。在原基发生后，负责指定不同花药细胞类型的分子过程尚不清楚。也不知道在特定的花药细胞类型中表达的基因组是如何在花药发育过程中被协调激活的。本提案中概述的实验将利用嵌合的细胞毒性和抗细胞毒性基因来解决细胞/细胞相互作用过程在指定花药细胞类型中的作用。其他实验将利用分子策略来识别激活花药组织绒毡层中几个非同源基因所需的调节电路的元件。这些实验的意义在于，它们应该提供对花药细胞类型分化所需的通讯过程的新见解，提供进入花药细胞类型分化所需的过程，提供进入负责这些细胞类型的指定的分子途径，并在植物发育过程中控制细胞特异性基因表达的机制上产生新的概念性信息。

Male reproductive processes in flowering plants occur in the anther. This organ is composed of several specialized tissues and cell types and is responsible for producing pollen grains that contain the sperm cells. Anther tissues form in an orderly pattern from cell lineages that are present within the floral meristem. These tissues differentiate from precursor cells that appear at specific locations, or territories, within the developing anther primordium. The molecular processes responsible for the specification of different anther cell types after primordium initiation are not known. Nor is it understood how gene sets that are expressed in specific anther cell types are activated coordinately during anther development. Experiments outlined in this proposal will utilize chimeric cytotoxic and anticytotoxic genes to address the role of cell/cell interaction processes in the specification of anther cell types. Other experiments will utilize molecular strategies to identify elements of the regulatory circuitry necessary to activate several non-homologous genes within one anther tissue, the tapetum. The significance of these experiments is that they should provide new insight into the communication processes required for the differentiation of anther cell types, provide entry into the processes required for the differentiation of anther cell types, provide entry into the molecular pathways responsible for the specification of these cell types, and generate new conceptual information on the mechanisms that control cell-specific gene expression during plant development.