Gene Enzyme and Physiological Characterization of shrunken-2 Isoalleles

9604612汉娜对玉米粒中淀粉合成的调控是汉娜博士多年来一直感兴趣的问题。对淀粉合成中突变的分析导致检测到ADP葡萄糖焦磷酸酶(AGP)的作用和活性中可能存在一个限速步骤。这项拟议的工作源于先前的支持结果，在这些支持中，已经确定了酶中决定其变构性质的区域(和氨基酸)。在接下来的课程中，汉纳博士将使用细菌表达系统来生产定向突变产生的酶，以获得关于酶的变构和催化域的详细知识，关于酶的两个亚单位之间的相互作用，并筛选第二位抑制突变。然后，他将返回到全植物分析，通过将玉米突变酶转化为含有缺失基因的背景。汉纳博士的工作在分析玉米淀粉突变和将遗传分析扩展到生物化学和植物生理学方面具有典范意义。

9604612 Hannah Regulation of starch synthesis in maize kernels is the interest of Dr. Hannah for many years. The analysis of mutants in starch synthesis resulted in the detection of a likely rate-limiting step in the action and activity of the enzyme, ADP glucose pyrophosphorylase (AGP). The proposed work originates from the results of prior support in which regions (and amino acids) in the enzyme have been identified which determine its allosteric properties. In the continuation, Dr. Hannah will use a bacterial expression system for the production of enzymes generated by directed mutagenesis to obtain detailed knowledge about allosteric and catalytic domains of the enzyme, about the interaction of the two subunits of the enzyme, and screen for second-site suppressor mutants. He will then return to whole plant analysis by corn transformation of mutant enzymes into a background which contains a deletion of the gene. Dr. Hannah's work has been paradigmatic for the analysis of maize starch mutants and the extension of genetic analysis into biochemistry and plant physiology.