title: Conidiation rhythm and light entrainment in superoxide dismutase mutant in Neurospora crassa.
abstract: Conidial formation in the filamentous fungus Neurospora crassa is regulated by nutritional conditions, light, and the circadian clock. We found that a sod-1 mutant, with a defective superoxide dismutase catalyzing the conversion of superoxide to hydrogen peroxide, had a slightly shorter period length than the wild type and clear conidial banding similar to a mutant of band (bd). However, unlike the bd mutant, the sod-1 mutant could sustain conidial banding with light pulses on a nutrient-rich medium, which involved an enhancement of the light-induced transcription of frequency (frq). sod-1 was hypersensitive to entrainment of the conidiation rhythm by light in race tubes. Furthermore, a frq(10); sod-1 double mutant showed conidiation rhythm in darkness and could be synchronized to light/dark cycles by the masking effect of light. These genetic analyses suggested that intracellular reactive oxygen species (ROS) act on circadian conidiation via multiple circadian clocks and output pathways.
authors: Kihara Institute for Biological Research, Graduate School of Integrated Science, Yokohama City University, 641-12 Maioka-cho, Totsuka-ku, Yokohama, Japan.
authors: Yusuke
authors: Y
authors: Yoshida
authors: Takashi
authors: T
authors: Maeda
authors: Bumkyu
authors: B
authors: Lee
authors: Kohji
authors: K
authors: Hasunuma
mesh_terms: D015152:Blotting, Northern; D002940:Circadian Rhythm; D005656:Fungal Proteins / Q000235:genetics; D015966:Gene Expression Regulation, Fungal / Q000528:radiation effects; D009154:Mutation; D009492:Neurospora crassa / Q000235:genetics / Q000502:physiology / Q000528:radiation effects*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013172:Spores, Fungal / Q000235:genetics / Q000254:growth & development / Q000528:radiation effects*; D013482:Superoxide Dismutase / Q000235:genetics*
chemical_list: C087405:FRQ protein, Neurospora crassa; D005656:Fungal Proteins; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D013482:Superoxide Dismutase