Abstract:
Farnesol is an isoprenoid intermediate in the mevalonate (MVA) pathway and is produced by the dephosphorylation of farnesyl diphosphate. Farnesol plays a central role in cell growth and differentiation, controls production of ubiquinone and ergosterol, and participates in the regulation of filamentation and biofilm formation. Despite these important functions, studies of farnesol in filamentous fungi are limited, and information on its effects on antifungal and/or biocontrol activity is scarce. In the present article, we identified the Trichoderma harzianum gene dpp1, encoding a diacylglycerol pyrophosphatase that catalyzes production of farnesol from farnesol diphosphate. We analyzed the function of dpp1 to address the importance of farnesol in Trichoderma physiology and ecology. Overexpression of dpp1 in T. harzianum caused an expected increase in farnesol production as well as a marked change in squalene and ergosterol levels, but overexpression did not affect antifungal activity. In interaction with plants, a dpp1-overexpressing transformant acted as a sensitizing agent in that it up-regulated expression of plant defense salicylate-related genes in the presence of a fungal plant pathogen. In addition, toxicity of farnesol on Trichoderma and plants was examined. Finally, a phylogenetic study of dpp1 was performed to understand its evolutionary history as a primary metabolite gene. This article represents a step forward in the acquisition of knowledge on the role of farnesol in fungal physiology and in fungus-environment interactions.
摘要:
法尼醇是甲羟戊酸(MVA)途径中的类异戊二烯中间体,并且通过法尼基二磷酸的去磷酸化产生。法尼醇在细胞生长和分化中起着核心作用,控制泛醌和麦角甾醇的产生,并参与成丝和生物膜形成的调节。尽管有这些重要的功能,金尼醇在丝状真菌中的研究是有限的,并且关于其对抗真菌和/或生物防治活性的影响的信息很少。在本文中,我们鉴定了哈茨木霉基因dpp1,编码二酰甘油焦磷酸酶,催化法尼醇二磷酸产生法尼醇.我们分析了dpp1的功能,以解决法尼醇在木霉生理和生态学中的重要性。harzianum中dpp1的过表达导致预期的法尼醇产量增加以及角鲨烯和麦角甾醇水平的显著变化。但过表达不影响抗真菌活性。在与植物的互动中,过表达dpp1的转化体作为致敏剂,因为它在真菌植物病原体存在下上调植物防御水杨酸盐相关基因的表达。此外,研究了法尼醇对木霉属和植物的毒性。最后,进行了dpp1的系统发育研究,以了解其作为主要代谢产物基因的进化史。本文代表了在获取有关法尼醇在真菌生理学和真菌与环境相互作用中的作用的知识方面迈出的一步。