Developmental Biology and Genetics of the Maize Leaf

本研究的核心是玉米叶片发育突变体的特征。其中两个通过转座子标记克隆。本建议所处理的问题是：所研究的叶片发育突变体是否如假设的那样，在细胞年龄特性上发生了改变，还是在位置特性上发生了改变？植物的发育时间保持问题尤其容易解决。2. 动物的发育区室概念是否适用于植物？弗里林博士将在基因镶嵌研究中使用显性侏儒来解决这个问题。3. 血管原细胞是其他叶细胞命运的主要诱导因子吗？表皮在诱导分化成特定的细胞类型之前是一张信息“空白页”吗？Freeling博士将使用详细的静脉谱系图、周周嵌合分析和无法吻合中间静脉的突变体来解决这两个相关的问题。这些研究将建立玉米叶片作为一个强大的发育系统，适用于突变分析以及细胞生物学和胚胎学研究。对这些水平突变体的研究将为正在进行的发育基因调控的分子描述研究提供一个背景。

The core of this study involves the characterization of leaf developmental mutants in maize. Two have been cloned via transposon-tagging. The questions addressed in this proposal are: 1.Are the leaf development mutants under study altered in cellular age-identity, as hypothesized, or in position-identity? Problems of developmental time-keeping are especially approachable in plants. 2. Does the animal concept of developmental compartments apply to plants? Dr. Freeling will address this question using a dominant dwarf in genetic mosaic studies. 3. Are the provascular cells the primary inducers of other leaf cell fates? Is the epidermis an information "blank sheet" until induced to differentiate into particular cell types? Dr. Freeling will approach these two related question using detailed vein lineage maps, periclinal chimeric analyses, and mutants that fail to anastomose intermediate veins. %%% These studies will establish the maize leaf as a powerful developmental system amenable to mutant analysis as well as for cell biological, and embryological studies. The approach to the mutants at these levels will provide a context for the on-going studies on the molecular descriptions of developmental gene regulation.