Aspergillus oryzae atfA controls conidial germination and stress tolerance.
We compared atfA and atfB, the genes encoding the respective ATF/CREB-type transcription factors in Aspergillus oryzae. The germination ratio of DeltaatfA conidia was low without any stress, unlike that of DeltaatfB conidia. The DeltaatfA conidia were more sensitive to oxidative stress than the DeltaatfB conidia, which are also sensitive to oxidative stress. We compared the gene expressions of these strains by using a DNA microarray, GeneChip. Almost all the genes regulated by atfB were also regulated by atfA, but atfA also regulated many genes that were not regulated by atfB, including some genes putatively involved in oxidative stress resistance. The level of glutamate, the major amino acid in A. oryzae conidia, was significantly low only in the DeltaatfA conidia, and the glycerol accumulation during germination was not observed only in the DeltaatfA strain. We therefore concluded that atfA is involved in germination via carbon and nitrogen source metabolism.
Sakamoto
Kazutoshi
K
National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima, Japan. k.sakamoto@nrib.go.jp
Iwashita
Kazuhiro
K
Yamada
Osamu
O
Kobayashi
Ken
K
Mizuno
Akihiro
A
Akita
Osamu
O
Mikami
Shigeaki
S
Shimoi
Hitoshi
H
Gomi
Katsuya
K
D051696:Activating Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000378:metabolism; D001236:Aspergillus oryzae / Q000235:genetics / Q000502:physiology*; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D005990:Glycerol / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D018384:Oxidative Stress; D011401:Promoter Regions, Genetic; D016415:Sequence Alignment; D013172:Spores, Fungal / Q000235:genetics / Q000502:physiology*; D013312:Stress, Physiological; D014199:Trehalose / Q000378:metabolism
D051696:Activating Transcription Factors; D000596:Amino Acids; D005656:Fungal Proteins; D014199:Trehalose; D002374:Catalase; D005990:Glycerol