XIA Wen-Qiang*, GAO Li-Dan*, ZHANG Ya-Fen, YU Xiao-Ping, YE Zi-Hong**
Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine /College of Life Sciences, China Jiliang University, Hangzhou 310018, China
Abstract：Ustilago maydis is a well-established model system for biotrophic fungal plant pathogens. Domesticated maize and its wild progenitor teosinte (both Zea mays) are its obligated host plant. U. maydis establishes a comprehensive relationship with their host to support the infection process. Central to this strategy is to secrete an arsenal of protein effectors, which can suppress plant defense responses, modulate host metabolism, or induce plant tumors to facilitate the growth and development of the pathogen. Since the functional redundancy and the lack of recognizable domain, it was very difficult for effector identification and functional study. With the development of next-generation sequencing, comparative transcriptome and comparative genome provide an excellent chance for effector research. In this review, we discuss new insights into the biological function, transcriptional regulation, and post-translation modification of effectors. Highlight its functions in a preventing cell wall reinforcement, suppressing reactive oxygen species (ROS) accumulation and programmed cell death, regulating hormone metabolism, and inducing plant tumors. This paper is helpful to understand the infection strategy of biotrophic fungi and identify relevant effectors.
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