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.

• Authors: Thaila Fernanda Dos Reis, Laura Mellado, Jessica M Lohmar, Lilian Pereira Silva, Jing-Jiang Zhou, Ana M Calvo, Gustavo H Goldman, Neil A Brown
• Journal: PLoS genetics (PLoS Genet) Vol. 15 Issue 10 Pg. e1008419 (10 2019) ISSN: 1553-7404 [Electronic] United States
• PMID: 31609971 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Fungal Proteins
• Receptors, G-Protein-Coupled
• Sterigmatocystin
• Carbon
• Glucose

Topics

• Adaptation, Physiological (radiation effects)
• Aspergillus nidulans (physiology)
• Carbon (metabolism)
• Fungal Proteins (metabolism)
• Gene Expression Profiling
• Gene Expression Regulation, Fungal (radiation effects)
• Glucose (metabolism)
• Light
• Morphogenesis
• Receptors, G-Protein-Coupled (metabolism)
• Spores, Fungal (growth & development, radiation effects)
• Sterigmatocystin (biosynthesis)