Biosynthesis of Floral Scent Benzenoid Esters

许多植物的花通过合成和散发香味来吸引传粉者，如果植物不能成功地赢得当地传粉者的注意，就会导致低结实率。苯甲酸酯，包括甲基水杨酸酯，是最常见和最有效的气味挥发物之一，花释放出来吸引飞蛾和其他昆虫授粉。然而，在首席研究员的实验室最近的工作之前，人们对植物如何合成它们知之甚少。在这个项目中，皮切斯基博士的实验室将继续他的实验室最近发现的两种苯酯形成酶的生化和结构表征，包括催化甲基水杨酸形成的酶。他们还将确定并表征在该途径的早期步骤中起作用的关键酶，该酶负责将苯甲酸前体的碳骨架从C9缩短为C7。除了这些酶的生化特性外，它们还将决定它们的细胞和亚细胞定位以及编码它们的基因的调节模式。该项目将大大提高对这一重要植物生化途径的理解，并且该基因的分离最终可能导致操纵农学上重要作物的花挥发物的能力，以提高昆虫传粉者的访问频率，从而提高果实/种子产量。

PicherskyThe flowers of many plants synthesize and emit scent as a means of attracting pollinators, and low seed/fruit set could result if the plant is not successful in the competition for the attention of locally available pollinators. Benzenoid esters, including methylsalicylate, are among the most common, and most efficacious, scent volatiles that flowers emit to attract moths and other insect pollinators. Yet, until the recent work from the lab of the principle investigator, little had been known about how plants synthesize them. In this project, Dr. Pichersky's lab will continue the biochemical and structural characterization of two benzenoid ester-forming enzymes that his lab recently identified, including the enzyme that catalyzes the formation of methylsalicylate. They will also identify and characterize a key enzyme that acts at an earlier step in the pathway and that is responsible for the shortening of the carbon skeleton of the benzoic acid precursor from C9 to C7. In addition to the biochemical characterization of these enzymes, they will determine their cellular and subcellular localization and the mode of regulation of the genes encoding them.This project should result in a substantial enhancement of the understanding of this important plant biochemical pathway, and the isolation of the genes could eventually lead to the ability to manipulate floral volatiles in agronomically important crops to enhance visitation frequencies by insect pollinators and thereby increase fruit/seed yields.