内生真菌与寄主互惠共生的分子机制

doi:10.11686/cyxb2016176

摘要/Abstract

摘要： 在自然界中广泛存在真菌与植物形成的共生体,这种共生作用可以引起真菌和其寄主植物发生重要的适应性变化。内生真菌与冷季型草坪草高羊茅和黑麦草形成互惠共生体,与病原真菌生长方式的不同,内生真菌仅在寄主细胞间生存,与寄主保持协同生长,这些独特的生长方式使得内生真菌生活在植物特定组织内,从不侵染植物细胞,因而寄主缺乏防御反应,二者通过信号交流和调控建立并维持这种互惠共生关系。内生真菌和寄主信号交流包括了多种已知的途径,其中确定的有活性氧调控途径,有丝分裂原活化蛋白(mitogen-activated protein,MAP) 激酶级联信号途径及cAMP和Ca²⁺作为第二信使的信号途径,本文综述了通过显微镜等各种技术确定的内生真菌在寄主细胞间的生长方式和目前通过基因敲除技术已知的与维持内生真菌与寄主互惠共生相关的基因,期望为深入揭示内生真菌与寄主的信号转导途径提供参考。

Abstract: Symbioses between fungi and plants have occurred naturally and widely during long-term evolution. This relationship makes both fungi and plants more adaptable to environmental changes. Endophytes form symbiotic associations with temperate grasses including Festuca and Lolium spp. The establishment and maintenance of these mutualistic associations involves mutual communication between the endophyte and the host. The growth of these endophytes is strictly intercellular and tightly regulated, and is synchronized with the growth of the host. Using this unique growth pattern, the endophyte does not trigger the host defense response and establishes a precise communication and regulatory pathway with the host. This communication will likely involve many well-known signaling pathways. Mitogen-activated protein kinase (MAPK) cascades and second messenger signaling pathways involving cAMP and calcium are the main pathways for signal transduction. Here, we review the endophyte growth pattern in the host, and discuss research on the genes involved in signaling pathways between the endophyte and host using modern molecular technologies. The information gained so far can be used to predict the possible functions of these pathways in endophyte associations, and provides a reference for further in-depth analyses of the communication network between the endophyte and the host.

田沛, 南志标. 内生真菌与寄主互惠共生的分子机制[J]. 草业学报, 2017, 26(4): 196-210.

TIAN Pei, NAN Zhi-Biao. Signaling in the mutualistic symbiotic interaction between endophytes and their hosts[J]. Acta Prataculturae Sinica, 2017, 26(4): 196-210.

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