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GPCR-mediated glucose sensing system regulates light-dependent fungal development and mycotoxin production.

ABSTRACT: Microorganisms sense environmental fluctuations in nutrients and light, coordinating their growth and development accordingly. Despite their critical roles in fungi, only a few G-protein coupled receptors (GPCRs) have been characterized. The Aspergillus nidulans genome encodes 86 putative GPCRs. Here, we characterise a carbon starvation-induced GPCR-mediated glucose sensing mechanism in A. nidulans. This includes two class V (gprH and gprI) and one class VII (gprM) GPCRs, which in response to glucose promote cAMP signalling, germination and hyphal growth, while negatively regulating sexual development in a light-dependent manner. We demonstrate that GprH regulates sexual development via influencing VeA activity, a key light-dependent regulator of fungal morphogenesis and secondary metabolism. We show that GprH and GprM are light-independent negative regulators of sterigmatocystin biosynthesis. Additionally, we reveal the epistatic interactions between the three GPCRs in regulating sexual development and sterigmatocystin production. In conclusion, GprH, GprM and GprI constitute a novel carbon starvation-induced glucose sensing mechanism that functions upstream of cAMP-PKA signalling to regulate fungal development and mycotoxin production.

SUBMITTER: Dos Reis TF

PROVIDER: S-EPMC6812930 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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GPCR-mediated glucose sensing system regulates light-dependent fungal development and mycotoxin production.

Dos Reis Thaila Fernanda TF Mellado Laura L Lohmar Jessica M JM Silva Lilian Pereira LP Zhou Jing-Jiang JJ Calvo Ana M AM Goldman Gustavo H GH Brown Neil A NA

PLoS genetics 20191014 10

Microorganisms sense environmental fluctuations in nutrients and light, coordinating their growth and development accordingly. Despite their critical roles in fungi, only a few G-protein coupled receptors (GPCRs) have been characterized. The Aspergillus nidulans genome encodes 86 putative GPCRs. Here, we characterise a carbon starvation-induced GPCR-mediated glucose sensing mechanism in A. nidulans. This includes two class V (gprH and gprI) and one class VII (gprM) GPCRs, which in response to gl ...[more]

PMID: 31609971

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GPCR-mediated glucose sensing system regulates light-dependent fungal development and mycotoxin production.

Publications

GPCR-mediated glucose sensing system regulates light-dependent fungal development and mycotoxin production.

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