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RgsD negatively controls development, toxigenesis, stress response, and virulence in Aspergillus fumigatus.

ABSTRACT: The regulator of G protein signaling (RGS) domain proteins generally attenuate heterotrimeric G protein signaling, thereby fine-tune the duration and strength of signal transduction. In this study, we characterize the functions of RgsD, one of the six RGS domain proteins present in the human pathogenic fungus Aspergillus fumigatus. The deletion (?) of rgsD results in enhanced asexual sporulation coupled with increased mRNA levels of key developmental activators. Moreover, ?rgsD leads to increased spore tolerance to UV and oxidative stress, which might be associated with the enhanced expression of melanin biosynthetic genes and increased amount of melanin. Yeast two-hybrid assays reveal that RgsD can interact with the three G? proteins GpaB, GanA, and GpaA, showing the highest interaction potential with GpaB. Importantly, the ?rgsD mutant shows elevated expression of genes in the cAMP-dependent protein kinase A (PKA) pathway and PKA catalytic activity. The ?rgsD mutant also display increased gliotoxin production and elevated virulence toward Galleria mellonella wax moth larvae. Transcriptomic analyses using RNA-seq reveal the expression changes associated with the diverse phenotypic outcomes caused by ?rgsD. Collectively, we conclude that RgsD attenuates cAMP-PKA signaling pathway and negatively regulates asexual development, toxigenesis, melanin production, and virulence in A. fumigatus.

SUBMITTER: Kim Y

PROVIDER: S-EPMC6349852 | biostudies-other | 2019 Jan

REPOSITORIES: biostudies-other

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RgsD negatively controls development, toxigenesis, stress response, and virulence in Aspergillus fumigatus.

Kim Young Y Lee Min-Woo MW Jun Sang-Cheol SC Choi Yong-Ho YH Yu Jae-Hyuk JH Shin Kwang-Soo KS

Scientific reports 20190128 1

The regulator of G protein signaling (RGS) domain proteins generally attenuate heterotrimeric G protein signaling, thereby fine-tune the duration and strength of signal transduction. In this study, we characterize the functions of RgsD, one of the six RGS domain proteins present in the human pathogenic fungus Aspergillus fumigatus. The deletion (Δ) of rgsD results in enhanced asexual sporulation coupled with increased mRNA levels of key developmental activators. Moreover, ΔrgsD leads to increase ...[more]

PMID: 30692551

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Dataset Information

RgsD negatively controls development, toxigenesis, stress response, and virulence in Aspergillus fumigatus.

Publications

RgsD negatively controls development, toxigenesis, stress response, and virulence in Aspergillus fumigatus.

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