Trehalose synthesis and metabolism are required at different stages of plant infection by Magnaporthe grisea
Trehalose synthesis and metabolism are required at different stages of plant infection by Magnaporthe grisea
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DOI：
10.1093/emboj/cdg018
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发表时间：
2003-01-15
期刊：
影响因子：
11.4
通讯作者：
Talbot, NJ
中科院分区：
文献类型：
--
作者：
Foster, AJ;Jenkinson, JM;Talbot, NJ
探讨了稻瘟病菌的海藻糖代谢与致病力的关系。为了确定海藻糖合成在发病机制中的作用，我们鉴定并删除了编码海藻糖-6-磷酸合酶的TPS 1。一个Deltatps 1突变体不能合成海藻糖，产孢差，致病性大大减弱。Deltatps 1产生的附着胞不能有效地发育完全膨压或精心的穿透菌丝。为了确定后续海藻糖分解的作用，我们删除了NTH 1，其编码中性海藻糖酶。nth 1突变体正常侵染植物，但由于定殖植物组织的能力降低而表现出减弱的致病性。还鉴定了第二种海藻糖酶，其在感染相关发育期间在海藻糖上生长和细胞内海藻糖的动员都需要。TRE 1编码一种位于细胞壁的酶，具有中性和酸性海藻糖酶的特征，但不具有致病性。我们的研究结果表明，海藻糖的合成，但不是其随后的分解，是所需的主要植物感染稻瘟病菌，而海藻糖降解是重要的有效发展的真菌在植物组织中的初始感染。
The relationship of trehalose metabolism to fungal virulence was explored in the rice blast fungus Magnaporthe grisea. To determine the role of trehalose synthesis in pathogenesis, we identified and deleted TPS1, encoding trehalose-6-phosphate synthase. A Deltatps1 mutant failed to synthesize trehalose, sporulated poorly and was greatly attenuated in pathogenicity. Appressoria produced by Deltatps1 did not develop full turgor or elaborate penetration hyphae efficiently. To determine the role of subsequent trehalose breakdown, we deleted NTH1, which encodes a neutral trehalase. Nth1 mutants infected plants normally, but showed attenuated pathogenicity due to a decreased ability to colonize plant tissue. A second trehalase was also identified, required both for growth on trehalose and mobilization of intracellular trehalose during infection-related development. TRE1 encodes a cell wall-localized enzyme with characteristics of both neutral and acidic trehalases, but is dispensable for pathogenicity. Our results indicate that trehalose synthesis, but not its subsequent breakdown, is required for primary plant infection by M.grisea, while trehalose degradation is important for efficient development of the fungus in plant tissue following initial infection.