Dataset Information

Characterization of gprK Encoding a Putative Hybrid G-Protein-Coupled Receptor in Aspergillus fumigatus.

ABSTRACT: The G-protein-coupled receptor (GPCR) family represents the largest and most varied collection of membrane embedded proteins that are sensitized by ligand binding and interact with heterotrimeric G proteins. Despite their presumed critical roles in fungal biology, the functions of the GPCR family members in the opportunistic human pathogen Aspergillus fumigatus are largely unknown, as only two (GprC and GprD) of the 15 predicted GPCRs have been studied. Here, we characterize the gprK gene, which is predicted to encode a hybrid GPCR with both 7-transmembrane and regulator of G-protein signaling (RGS) domains. The deletion of gprK causes severely impaired asexual development coupled with reduced expression of key developmental activators. Moreover, ?gprK results in hyper-activation of germination even in the absence of carbon source, and elevated expression and activity of the protein kinase A PkaC1. Furthermore, proliferation of the ?gprK mutant is restricted on the medium when pentose is the sole carbon source, suggesting that GprK may function in external carbon source sensing. Notably, the absence of gprK results in reduced tolerance to oxidative stress and significantly lowered mRNA levels of the stress-response associated genes sakA and atfA. Activities of catalases and SODs are severely decreased in the ?gprK mutant, indicating that GprK may function in proper activation of general stress response. The ?gprK mutant is also defective in gliotoxin (GT) production and slightly less virulent toward the greater wax moth, Galleria mellonella. Transcriptomic studies reveal that a majority of transporters are down-regulated by ?gprK. In summary, GprK is necessary for proper development, GT production, and oxidative stress response, and functions in down-regulating the PKA-germination pathway.

SUBMITTER: Jung MG

PROVIDER: S-EPMC5008803 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Characterization of gprK Encoding a Putative Hybrid G-Protein-Coupled Receptor in Aspergillus fumigatus.

Jung Mun-Gu MG Kim Sung Su SS Yu Jae-Hyuk JH Shin Kwang-Soo KS

PloS one 20160901 9

The G-protein-coupled receptor (GPCR) family represents the largest and most varied collection of membrane embedded proteins that are sensitized by ligand binding and interact with heterotrimeric G proteins. Despite their presumed critical roles in fungal biology, the functions of the GPCR family members in the opportunistic human pathogen Aspergillus fumigatus are largely unknown, as only two (GprC and GprD) of the 15 predicted GPCRs have been studied. Here, we characterize the gprK gene, which ...[more]

PMID: 27584150

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Dataset Information

Characterization of gprK Encoding a Putative Hybrid G-Protein-Coupled Receptor in Aspergillus fumigatus.

Publications

Characterization of gprK Encoding a Putative Hybrid G-Protein-Coupled Receptor in Aspergillus fumigatus.

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