Molecular Analysis of Genes Expressed in the Floral Meristem

这项建议旨在鉴定、分离和鉴定在花分生组织中特异表达的基因。烟草“薄细胞层”(TCL)组织培养体系将用于生产含有花分生组织的外植体。TCL外植体在花卉培养条件下，根据以下方案产生最多15朵完全分化的功能花。第7天：细胞分裂活跃；第13天：形成有组织的分生组织；第20天：分化器官可见。从第13天的花TCL外植体建立的差异筛选将被用于分离在培养第13天转录表达的基因的克隆，而不是在培养的第7天。通过这种方法分离的潜在分生组织特异性基因将用原位杂交来鉴定那些在花分生组织中表达的基因。在稳定的植物转化的促进下，人们将对感兴趣的基因进行分子和体外突变分析，以确定基因在花启动过程中的调控和功能机制。这项工作将通过提供控制发育调控基因表达的因素的证据，并洞察改变植物生长策略所需的基因类型，从而极大地提高我们对植物发育中基因表达的理解。

This proposal is designed to identify, isolate, and characterized genes specifically expressed in floral meristems. The novel tobacco (Nicotiana tabacum) "Thin Cell Layer" (TCL) tissue culture system will be used to produce explants containing floral meristems. TCL explants in floral culture conditions produce up to 15 fully differentiated and functional flowers according to the following scheme. Day 7:active cell division; Day 13: organized meristems formed, Day 20: differentiated organs visable. Differential screening of a cDNA library made from Day 13 floral TCL explants will be used to isolate clones for genes transcriptionally expressed at Day 13, but not a Day 7, of culture. Potential meristematic specific genes isolated by this approach will be characterized using in situ hybridization to identify those expressed in floral meristems. Genes of interest will be subjected to molecular and in vitro mutational analysis, facilitated by stable plant transformation, to determine the mechanisms of gene regulation and function during floral initiation. This work should greatly improve our understanding of gene expression in plant development by providing evidence of the factors which control developmentally regulated gene expression, and giving insight to the types of genes required to change the strategy of plant growth.