Availability and efficient utilization of host-derived nutrients by pathogens decide the fate of host-pathogen interaction. In Magnaporthe oryzae, N-acetylglucosamine (GlcNAc) catabolic pathway was found essential for successful host colonization and pathogenicity. GlcNAc catabolic enzymes hexokinase, GlcNAc-6-phosphate deacetylase (MoDac) and GlcN-6-phosphate deaminase (MoDeam) are encoded in a genomic cluster in M. oryzae and several phytopathogenic fungi. However, transcriptional regulation of GlcNAc catabolic pathway was not understood. We identified a conserved Ndt80/PhoG-like transcriptional regulator as a part of the GlcNAc catabolic gene cluster in M. oryzae and other fungi. We found that MoNdt80 is essential for GlcNAc utilization and pathogenicity of M. oryzae. Unlike WT, ΔMoNdt80 failed to induce transcription of GlcNAc catabolic pathway genes in response to GlcNAc. MoNdt80 could bind to a specific cis-acting consensus sequence GNCRCAAA[AT], present in the promoter of MoDac, MoDeam and β-hexosaminidase (MoHex). Further, comparative RNA-sequencing analysis using WT and ΔMoNdt80 revealed a large set of GlcNAc responsive genes that are under the transcriptional control of MoNdt80. These genes encoded GlcNAc catabolic enzymes, transporters and cell wall degrading enzymes which are required for hyphal growth expansion during host colonization. Overall, these results suggest MoNdt80 mediated transcriptional regulation of GlcNAc catabolic pathway is essential for successful host colonization and pathogenesis.

病原体对宿主来源营养素的可用性和有效利用决定了宿主与病原体相互作用的命运。在稻瘟病菌中，发现N-乙酰氨基葡萄糖（GlcNAc）分解代谢途径对于成功的宿主定殖和致病性至关重要。GlcNAc分解代谢酶己糖激酶，GlcNAc-6磷酸脱乙酰基酶（MoDac）和GlcN-6磷酸脱氨酶（MoDeam）在米曲霉和几种植物病原真菌的基因组簇中编码。但是，GlcNAc分解代谢途径的转录调控尚不清楚。我们确定了保守的Ndt80 / PhoG样转录调节因子，作为米曲霉和其他真菌中GlcNAc分解代谢基因簇的一部分。我们发现MoNdt80对米曲霉GlcNAc的利用和致病性至关重要。与WT不同，ΔMoNdt80不能响应GlcNAc诱导GlcNAc分解代谢途径基因的转录。MoNdt80可以结合特定顺式作用共有序列GNCRCAAA [AT]，该序列存在于MoDac，MoDeam和β-己糖胺酶（MoHex）的启动子中。此外，使用WT和ΔMoNdt80进行比较性RNA测序分析揭示了大量在MoNdt80的转录控制下的GlcNAc响应基因。这些基因编码GlcNAc分解代谢酶，转运蛋白和细胞壁降解酶，这些是宿主定殖期间菌丝生长扩展所必需的。总体而言，这些结果表明MoNdt80介导的GlcNAc分解代谢途径的转录调控对于成功的宿主定植和发病机理至关重要。