Glycogen metabolic genes are involved in trehalose-6-phosphate synthase-mediated regulation of pathogenicity by the rice blast fungus Magnaporthe oryzae.
Glycogen metabolic genes are involved in trehalose-6-phosphate synthase-mediated regulation of pathogenicity by the rice blast fungus Magnaporthe oryzae.
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DOI：
10.1371/journal.ppat.1003604
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发表时间：
2013
期刊：
影响因子：
6.7
通讯作者：
Talbot NJ
中科院分区：
文献类型：
--
作者：
Badaruddin M;Holcombe LJ;Wilson RA;Wang ZY;Kershaw MJ;Talbot NJ
稻瘟病菌是水稻稻瘟病的病原菌。在此，我们发现糖原代谢基因在植物侵染稻瘟病菌过程中起着重要作用。分别编码淀粉葡萄糖苷酶和糖原磷酸化酶的AGL1和GPH1的靶向缺失，阻止了附着胞发育过程中糖原储备的动员，并导致稻瘟病菌引起稻瘟病的能力显著降低。相反，编码糖原合成酶的GSN1的靶向突变显著减少了细胞内糖原的合成，但对真菌的致病性没有影响。我们发现AGL1和GPH1的缺失导致TPS1和TPS3的表达减少，TPS1和TPS3编码海藻糖-6-磷酸合成酶复合体的成分，在米曲霉中起到遗传开关的作用。TPS1对葡萄糖-6-磷酸水平和NADP/NADPH的平衡做出反应，与核磁共振转录抑制物一起调节毒力相关基因的表达。我们发现，NMR3转录抑制基因的缺失部分恢复了对Δag11ΔGph1突变体的毒力，这表明糖原代谢基因是操作依赖于NADPH的遗传开关所必需的。稻瘟病菌会导致水稻的一种毁灭性疾病，称为稻瘟病。每年，稻瘟病摧毁了全球水稻潜在收成的近四分之一。这种真菌通过形成一种名为附着胞的特殊感染结构来感染水稻，这种结构会物理地破坏水稻叶片坚硬的外层角质层。在缺乏营养源的情况下，木兰花可以形成附着体。因此，我们正在研究这种真菌如何利用其孢子中的能量储存来为其最初的生长和发育提供燃料。糖原是真菌中一种关键的储存化合物，在这项研究中，我们研究了稻瘟菌中如何发生糖原分解。我们已经证明，降解细胞中糖原储存的两种主要酶在稻瘟病中是重要的。然而，我们也发现，一种合成自身糖原能力严重受损的真菌菌株仍然可以正常感染植物。为了解释这些明显相互矛盾的发现，我们探索了糖原分解的调节作用，并提供了证据表明，糖原代谢是最近描述的木兰花毒力相关遗传开关的关键调节因子，该开关由一种名为海藻糖-6-磷酸合成酶的酶操纵。
The filamentous fungus Magnaporthe oryzae is the causal agent of rice blast disease. Here we show that glycogen metabolic genes play an important role in plant infection by M. oryzae. Targeted deletion of AGL1 and GPH1, which encode amyloglucosidase and glycogen phosphorylase, respectively, prevented mobilisation of glycogen stores during appressorium development and caused a significant reduction in the ability of M. oryzae to cause rice blast disease. By contrast, targeted mutation of GSN1, which encodes glycogen synthase, significantly reduced the synthesis of intracellular glycogen, but had no effect on fungal pathogenicity. We found that loss of AGL1 and GPH1 led to a reduction in expression of TPS1 and TPS3, which encode components of the trehalose-6-phosphate synthase complex, that acts as a genetic switch in M. oryzae. Tps1 responds to glucose-6-phosphate levels and the balance of NADP/NADPH to regulate virulence-associated gene expression, in association with Nmr transcriptional inhibitors. We show that deletion of the NMR3 transcriptional inhibitor gene partially restores virulence to a Δagl1Δgph1 mutant, suggesting that glycogen metabolic genes are necessary for operation of the NADPH-dependent genetic switch in M. oryzae. The fungus Magnaporthe oryzae causes a devastating disease of rice called blast. Each year, rice blast disease destroys almost a quarter of the potential global rice harvest. The fungus infects rice plants by elaborating a special infection structure called an appressorium, which physically breaks the tough outer cuticle of a rice leaf. Magnaporthe can develop appressoria in the absence of a nutrient source. We are therefore studying how the fungus utilizes energy stores in its spores to fuel its initial growth and development. Glycogen is a key storage compound in fungi and in this study we have investigated how glycogen breakdown occurs in the rice blast fungus. We have shown that the two major enzymes that degrade cellular stores of glycogen are important in rice blast disease. However, we also found that a strain of the fungus which is severely impaired in its ability to synthesize its own glycogen can still infect plants normally. To explain these apparently contradictory findings we explored the regulatory role of glycogen breakdown and provide evidence that glycogen metabolism is a key regulator of a recently described, virulence-associated genetic switch in Magnaporthe that is operated by an enzyme called trehalose-6-phosphate synthase.
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影响因子：
4.5
作者：
Fernandez J;Wright JD;Hartline D;Quispe CF;Madayiputhiya N;Wilson RA
通讯作者：
Wilson RA
DOI：
10.1073/pnas.85.23.8998
发表时间：
1988-12-01
影响因子：
11.1
作者：
FROHMAN, MA;DUSH, MK;MARTIN, GR
通讯作者：
MARTIN, GR
影响因子：
5.3
作者：
HWANG, PK;TUGENDREICH, S;FLETTERICK, RJ
通讯作者：
FLETTERICK, RJ
影响因子：
11.6
作者：
Adachi, K;Hamer, JE
通讯作者：
Hamer, JE
影响因子：
13.3
作者：
Deng, Yi Zhen;Ramos-Pamplona, Marilou;Naqvi, Naweed I.
通讯作者：
Naqvi, Naweed I.