Sugar-Modulated Expression and Developmental Control of Genes for Sucrose Metabolism

蔗糖代谢基因的糖调节表达和发育控制

• 批准号: 9507681
• 负责人: Karen Koch
• 金额: --
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-15 至 1999-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9507681&HistoricalAwards=false
• 关键词: Sugar; Modulated; Expression; Developmental; Control

9507681 Koch Adaptive plasticity of form is one of the most remarkable features of multicelled plants. At least one contributor to this flexibility appears to be the sensitivity of specific plant genes to sugar levels (ie. photosynthate availability). Among these are the genes for sucrose metabolizing enzymes. Import of translocated sucrose by growing organs can be strongly affected by the capacity for sucrose metabolism, which is catalyzed by only two known pathways in plant (invertase and the reversible sucrose synthase reaction). Under previous NSF grant, Dr. Koch has demonstrated that genes encoding both these enzymes in maize are carbohydrate-responsive, providing a potential mechanism for coarse adjustment of capacity for sucrose use relative to its overall availability. In addition, the newly cloned isozyme genes for invertase exhibit a differential carbohydrate responsiveness with surprising similarity to that observed among isozyme genes of sucrose synthase. In this project, Dr. Koch will address the significance of these developments using a combined molecular, genetic and physiological approach. Probes for an invertase gene family (putatively soluble) provide an opportunity to address the relationship between sugar-responsive gene expression and the widespread role of soluble invertases in initial growth by newly expanding sink tissues.

形态的适应性可塑性是多细胞植物最显著的特征之一。至少这种灵活性的一个贡献者似乎是特定植物基因对糖水平的敏感性。光合作用的产物可用性)。其中包括蔗糖代谢酶的基因。生长器官对易位蔗糖的进口受到蔗糖代谢能力的强烈影响，蔗糖代谢能力在植物中只有两种已知途径（转化酶和可逆蔗糖合成酶反应）催化。在之前的NSF资助下，Koch博士已经证明了玉米中编码这两种酶的基因是碳水化合物反应性的，这为相对于蔗糖的总体可用性粗略调整蔗糖使用能力提供了一种潜在的机制。此外，新克隆的转化酶同工酶基因表现出与蔗糖合酶同工酶基因惊人相似的差异碳水化合物反应性。在这个项目中，科赫博士将通过结合分子、遗传和生理方法来阐述这些发展的意义。转化酶基因家族（假定为可溶性）的探针提供了一个机会来解决糖反应性基因表达与可溶性转化酶在新扩张的汇组织初始生长中的广泛作用之间的关系。