Regulation of Cell Expansion in Arabidopsis Roots

这项工作的目标是了解调节植物器官发生的分子机制，这里的重点是根的形成。 已经从拟南芥中收集了许多突变体，这些突变体显示出根细胞的分裂、扩增和成熟的改变。 细胞扩增突变体本身可以细分为受环境影响的突变体和其他独立于环境条件但对内部（激素）线索做出反应的突变体。 其他突变体的扩展从纵向转移到径向扩展。 这项工作的重点是两个突变体，这是两个单独的类调制扩展生长，SABRE和COBRA的指示。 SABRE已被克隆。 设计实验以研究激素和位置对SABRE突变体表型表达的影响，以及转基因测定中基因产物的功能研究。COBRA将通过分子互补法克隆，包含该基因的56 kb区域已到手。 然后调节COBRA产物的量以测定其对表型的影响，最后筛选额外的突变体和抑制突变。 有了这项工作，Benedict博士将启动研究，将根细胞扩增的发育序列与基因产物及其位置和浓度效应的功能测定相结合。 对植物根细胞生长的研究将有助于我们对植物细胞生长特性的理解。

9604489 Benfey The goal of this work is to understand the molecular mechanisms that regulate organogenesis in plants, here with a focus on root formation. A number of mutants have been collected from Arabidopsis which show altered division, expansion and maturation of root cells. The class of cell expansion mutants can itself be sub-divided into mutants that are affected by the environment and others that are autonomous of the environmental condition, but respond to internal (hormonal) cues. Other mutants of expansion shift from longitudinal to radial expansion. The work focuses on two mutants that are indicative of tow individual classes of modulated expansion growth, SABRE and COBRA. SABRE has been cloned. Experiments are designed to study hormonal and positional effects on the expression of the SABRE mutant phenotype, and functional studies of the gene products in transgenic assays. COBRA will be cloned by molecular complementation, a 56 kb region which contains the gene is in hand. The amount of the COBRA product will then be modulated to gauge its effect on the phenotype and, finally, additional mutants and suppresser mutations will be screened for. With this work, Dr. Benfey will initiate studies that integrate the developmental sequence of root cell expansion with a functional assay of the gene product and its positional and concentration effects. Work on the growth of plant root cells will contribute to our understanding of plant cell growth characteristics.