Gibberellin Biosynthesis in Maize-Chemistry, Biochemistry and Genetics

玉米中的赤霉素生物合成——化学、生物化学和遗传学

• 批准号: 9306597
• 负责人: Bernard Phinney
• 金额: $ 28.5万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-09-01 至 1997-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9306597&HistoricalAwards=false
• 关键词: Gibberellin; Biosynthesis; Maize; Chemistry; Biochemistry

WPC 2 B P Z Courier 10cpi #| x =V x 6 X @ 8 ; X @ Canon LBP-8III (Additional) CALB8IAD.PRS x @ 0J zX @ #| x 2 % B X g F ` Courier 10cpi Courier Footnote 16cpi . ? x x x , =V x 6 X @ 8 ; X @ + H H H , S , H 6 X @ ; @ t 7 } 3 J4 s @ u $ u $ t 7 } 3 O4 K ^_ZY X P C~ } X C~ YX P C~ X PSQRVW 8 W u a c e g i i = : W _^ZY X 9306597 ` ` Phinney Through the pioneering use of single gene mutants, the PI has defined most of the steps in the pathway for gibberellins ? biosynthesis in maize vegetative shoots. We have shown that GA 1 is the major gibberellin controlling stem elongation in maize and that geranylgeranylpyrophosphate (GGPP) is metabolized to ? x copalylpyrophosphate (CPP0, ent kaurene, GA 12 , and G 1 via the early 13 hydroxylation branch pathway. This proposal describes metabolic experiments that will establish five remaining steps in this branch pathway and locate the steps blocked by our d2 , d3 , and anl mutants. In addition, metabolic studies with five members of a ? ` second branch pathway from GA 12 (the early non 3,13 hydroxylation pathway) will assess the importance of this pathway in the control of GA dependent growth in maize. The results from the proposed metabolic studies will provide a detailed description of the gibberellin biosynthetic pathways for maize shoots and will provide a model for studies with other plants. A search for additional GA (dwarf) mutants will be continued: these mutants are being generated by transposon tagging using the maize transposable element Ac. The location of the genetic blocks for the new mutants will be determined form bioassays, qualitative analysis of endogenous givverellins, and metabolic studies. An exciting and novel aspect of this proposal comes from the availability of transposon tagged dwarf mutants. The approach provides a convenient method for cloning specific genes for GA biosynthesis. These clones will be used in conjunction with conventional methods to isolate the enzymes that control specific steps in the biosynthetic pathway. %%% The objective of the research is to understand shoot elongation controlled by the class of plant hormones, the gibberellins (GAs). The strategy is to (i) identify the genes and the gene products for these steps in the pathway, and (iii) analyze the enzymes controlling these steps, and thereby provide information for the future manipulation of plant growth. ***

WPC 2 B P Z 10 cpi #|X =V x 6 X @ 8 ; X @ 佳能LBP-8III（附加） CALB8IAD.PRS X @ 0J zX @ #|X 2 % B X G F ` 16cpi. 16cpi . ? x x x， =V x 6 X @ 8 ; X @ + H H H， S、H 6 X @ ; @ 不 七、 3辆J 4 @ u $ u $ t 七、 3 O4 K ^_ZY X P C~ } X C~ YX P C~ X PSQRVW 8 W u a C e g i i =：W _^ZY X 9306597 ` ` Phinney通过开创性地使用单基因突变体，PI已经确定了赤霉素途径中的大多数步骤 ? 玉米营养芽的生物合成。 我们已经证明，GA 1 是控制玉米茎伸长的主要赤霉素，并且香叶基香叶基焦磷酸（GGPP）被代谢为 ? X 焦磷酸柯巴酯（CPP 0， ent New York，GA 12 ，G 1 通过早期13羟基化分支途径。 这个提议描述了代谢实验，将建立这个分支途径中的五个剩余步骤，并定位被我们的 D2 , D3 得双曲正弦值. ANL 变种人 此外，代谢研究与五名成员的一个 ? ` GA第二分支途径 12 (the早期非3，13羟基化途径）将评估该途径在控制玉米中GA依赖性生长中的重要性。 从拟议的代谢研究的结果将提供一个详细的描述赤霉素的生物合成途径的玉米芽，并将提供一个模型的研究与其他植物。将继续寻找额外的GA（矮）突变体：这些突变体是通过使用玉米转座因子Ac的转座子标记产生的。 新突变体的遗传区块的位置将通过生物测定、内源性givverelin的定性分析和代谢研究来确定。 这个提议的一个令人兴奋和新颖的方面来自转座子标记的矮突变体的可用性。 该方法为克隆GA生物合成的特异基因提供了一种简便的方法。 这些克隆将与常规方法结合使用，以分离控制生物合成途径中特定步骤的酶。%%% 本研究的目的是了解植物激素赤霉素（GAs）控制的芽伸长。 该策略是（i）鉴定途径中这些步骤的基因和基因产物，以及（iii）分析控制这些步骤的酶，从而为未来操纵植物生长提供信息。***