Molecular Genetic Analysis of Root Hair Elongation in Arabidopsis

拟议研究的目的是使用分子 遗传学的方法来了解发展的 顶端生长植物细胞增殖的调控机制 细胞为了实现这一目标，Schiefelbein博士选择研究 根毛的伸长，一个相对简单和可接近的细胞 在植物中打字。拟南芥的突变体已经被 离生的合成根毛，生长不规则 模式.他将首先集中在两个突变体（rhd 3和 rhd4）根据初步分析， 与根毛伸长密切相关的基因突变。 具体的研究方法包括：1） 超微结构、微丝和离子的表征 野生型和突变体根毛中的电流，2）连锁 RHD 3和RHD 4基因的新等位基因的分析和分离， 3)利用染色体进行基因的RFLP定位和分子克隆 用酵母人工染色体文库步移，和4） 其他基因分离和逐步表征 影响根毛伸长。这项研究的结果 预计将提供有关该机制的基本信息 调节尖端生长细胞的扩张，以及定义 控制植物根毛伸长的特殊基因。

The objective of the proposed research is to use a molecular genetic approach to gain an understanding of the developmental mechanisms that regulate cell expansion in tip-growing plant cells. To achieve this goal, Dr. Schiefelbein has chosen to study elongation in root hairs, a relatively simple and accessible cell type in plants. Mutants of Arabidopsis thaliana have been isolated that synthesize root hairs with irregular growth patterns. He will initially concentrate on two mutants (rhd3 and rhd4) that, based on preliminary analyses, are likely to harbor mutations in genes intimately involved in root hair elongation. The specific research approaches will include: 1) characterization of the ultrastructure, microfilaments, and ion currents in the wild type and mutant root hairs, 2) linkage analysis and isolation of new alleles of the RHD3 and RHD4 genes, 3) RFLP mapping and molecular cloning of the genes by chromosome walking with a yeast artificial chromosome library, and 4) isolation and stepwise characterization of additional genes affecting root hair elongation. The results from this research are expected to provide basic information on the mechanism regulating expansion in tip-growing cells, as well as to define specific genes governing root hair elongation in plants.