Title |
The putative C2H2 transcription factor RocA is a novel regulator of development and secondary metabolism in Aspergillus nidulans |
Author |
Dong Chan Won, Yong Jin Kim, Da Hye Kim, Hee-Moon Park*, and Pil Jae Maeng* |
Address |
Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon 34134, Republic of Korea |
Bibliography |
Journal of Microbiology, 58(7),574–587, 2020,
|
DOI |
10.1007/s12275-020-0083-7
|
Key Words |
C2H2 transcription factor, RocA, asexual development,
sexual development, secondary metabolism, Aspergillus
nidulans |
Abstract |
Multiple transcriptional regulators play important roles in
the coordination of developmental processes, including asexual
and sexual development, and secondary metabolism in the
filamentous fungus Aspergillus nidulans. In the present study,
we characterized a novel putative C2H2-type transcription
factor (TF), RocA, in relation to development and secondary
metabolism. Deletion of rocA increased conidiation and caused
defective sexual development. In contrast, the overexpression
of rocA exerted opposite effects on both phenotypes. Additionally,
nullifying rocA resulted in enhanced brlA expression
and reduced nsdC expression, whereas its overexpression
exerted the opposite effects. These results suggest that RocA
functions as a negative regulator of asexual development by
repressing the expression of brlA encoding a key asexual development
activator, but as a positive regulator of sexual development
by enhancing the expression of nsdC encoding a
pivotal sexual development activator. Deletion of rocA increased
the production of sterigmatocystin (ST), as well as the
expression of its biosynthetic genes, aflR and stcU. Additionally,
the expression of the biosynthetic genes for penicillin
(PN), ipnA and acvA, and for terrequinone (TQ), tdiB and
tdiE, was increased by rocA deletion. Thus, it appears that
RocA functions as a negative transcriptional modulator of the
secondary metabolic genes involved in ST, PN, and TQ biosynthesis.
Taken together, we propose that RocA is a novel
transcriptional regulator that may act either positively or negatively
at multiple target genes necessary for asexual and
sexual development and secondary metabolism. |