Principles of Carbon Catabolite Repression in the Rice Blast Fungus: Tps1, Nmr1-3, and a MATE–Family Pump Regulate Glucose Metabolism during Infection
نویسندگان
چکیده
Understanding the genetic pathways that regulate how pathogenic fungi respond to their environment is paramount to developing effective mitigation strategies against disease. Carbon catabolite repression (CCR) is a global regulatory mechanism found in a wide range of microbial organisms that ensures the preferential utilization of glucose over less favourable carbon sources, but little is known about the components of CCR in filamentous fungi. Here we report three new mediators of CCR in the devastating rice blast fungus Magnaporthe oryzae: the sugar sensor Tps1, the Nmr1-3 inhibitor proteins, and the multidrug and toxin extrusion (MATE)-family pump, Mdt1. Using simple plate tests coupled with transcriptional analysis, we show that Tps1, in response to glucose-6-phosphate sensing, triggers CCR via the inactivation of Nmr1-3. In addition, by dissecting the CCR pathway using Agrobacterium tumefaciens-mediated mutagenesis, we also show that Mdt1 is an additional and previously unknown regulator of glucose metabolism. Mdt1 regulates glucose assimilation downstream of Tps1 and is necessary for nutrient utilization, sporulation, and pathogenicity. This is the first functional characterization of a MATE-family protein in filamentous fungi and the first description of a MATE protein in genetic regulation or plant pathogenicity. Perturbing CCR in Δtps1 and MDT1 disruption strains thus results in physiological defects that impact pathogenesis, possibly through the early expression of cell wall-degrading enzymes. Taken together, the importance of discovering three new regulators of carbon metabolism lies in understanding how M. oryzae and other pathogenic fungi respond to nutrient availability and control development during infection.
منابع مشابه
Principles of Carbon Catabolite Repression in the Rice Blast Fungus: Tps1, Nmr1-3, and a MATEâ•fiFamily Pump Regulate Glucose Metabolism during Infection
Understanding the genetic pathways that regulate how pathogenic fungi respond to their environment is paramount to developing effective mitigation strategies against disease. Carbon catabolite repression (CCR) is a global regulatory mechanism found in a wide range of microbial organisms that ensures the preferential utilization of glucose over less favourable carbon sources, but little is known...
متن کاملAn NADPH-dependent genetic switch regulates plant infection by the rice blast fungus.
To cause rice blast disease, the fungus Magnaporthe oryzae breaches the tough outer cuticle of the rice leaf by using specialized infection structures called appressoria. These cells allow the fungus to invade the host plant and proliferate rapidly within leaf tissue. Here, we show that a unique NADPH-dependent genetic switch regulates plant infection in response to the changing nutritional and...
متن کاملTps1 regulates the pentose phosphate pathway, nitrogen metabolism and fungal virulence.
Trehalose fulfils a wide variety of functions in cells, acting as a stress protectant, storage carbohydrate and compatible solute. Recent evidence, however, indicates that trehalose metabolism may exert important regulatory roles in the development of multicellular eukaryotes. Here, we show that in the plant pathogenic fungus Magnaporthe grisea trehalose-6-phosphate (T6P) synthase (Tps1) is res...
متن کاملThe Sugar Sensor, Trehalose-6-Phosphate Synthase (Tps1), Regulates Primary and Secondary Metabolism during Infection by the Rice Blast Fungus: Will Magnaporthe oryzaeâ•Žs â•œSweet Toothâ•š become Its â•œAchillesâ•Ž Heelâ•š?
The Sugar Sensor, Trehalose-6-Phosphate Synthase (Tps1), Regulates Primary and Secondary Metabolism during Infection by the Rice Blast Fungus: Will Magnaporthe oryzae's " Sweet Tooth " become Its " Achilles' Heel " ?" (2011). Fungal Molecular Plant-Microbe Interactions. Paper 6. disparate cellular activities? To address this question, this review discusses our current understanding of tre-halos...
متن کامل