Expression profile of amylolytic genes in Aspergillus nidulans.
Aspergillus nidulans possessed 16 putative amylolytic genes consisting of 7 alpha-glucosidase (agdA-F), 7 alpha-amylase (amyA-F), and 2 glucoamylase (glaA and B) genes on the genome. Among them, the agdA, agdB, agdE, agdF, amyA, amyB, amyF, and glaB genes were induced by isomaltose. AmyR, a Zn(II)(2)Cys(6) transcription factor, was required for the induction. The isomaltose-inducible genes possessed at least one consensus sequence for AmyR binding, 5'-CGGN(8)CGG, on each promoter region. None of the amylolytic genes was induced by maltose. The mRNA levels of the amylolytic genes except for agdC, amyD, and amyG increased under carbon-starved conditions. Release from CreA-dependent carbon catabolite repression was the main cause of the increase, but, the mRNA levels of agdB, agdF, amyB, amyF, and glaB increased to some extent even in a creA mutant. Therefore, both CreA-dependent and -independent mechanisms are involved in the up-regulation of the amylolytic genes under carbon-starved conditions.
Nakamura
Takashi
T
Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Japan.
Maeda
Yuki
Y
Tanoue
Nami
N
Makita
Tomohiro
T
Kato
Masashi
M
Kobayashi
Tetsuo
T
D000681:Amylases / Q000235:genetics; D001233:Aspergillus nidulans / Q000201:enzymology / Q000235:genetics*; D002244:Carbon; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000502:physiology*; D005087:Glucan 1,4-alpha-Glucosidase / Q000235:genetics; D005959:Glucosidases / Q000235:genetics; D006026:Glycoside Hydrolases / Q000235:genetics*; D007534:Isomaltose / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis; D014512:Ureohydrolases / Q000378:metabolism
D012333:RNA, Messenger; D007534:Isomaltose; D002244:Carbon; D000681:Amylases; D005959:Glucosidases; D006026:Glycoside Hydrolases; D005087:Glucan 1,4-alpha-Glucosidase; D014512:Ureohydrolases; C019944:creatinase