Kid-1 participates in regulating ERK phosphorylation as a part of the circadian clock output in rat kidney.
Circadian clock genes play a role for the regulation of cell cycle, but the factors connecting clock to cell cycle are not fully understood. We found that mRNA of Kid-1--a zinc-finger-type transcriptional repressor was localized to cortical and juxtamedullary segments of tubules but not to glomeruli in the rat kidney. Kid-1 mRNA showed robust circadian oscillation with a peak at ZT16. Under temporal restricted feeding, the phase of the oscillation shifted along with mRNAs of the clock genes--Per1 and Per2. The rhythm of S-phase in cell cycle disappeared in the kidney under the restricted feeding. The level of phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 was rhythmic with a peak at ZT16 in the kidney. We found that knockdown and overexpression of Kid-1 in NRK52E (normal rat kidney epithelial) cells induced and reduced the phosphorylation of ERK1/2, respectively. The data suggest that clock-controlled Kid-1 regulates the cell cycle of proliferating renal tubular epithelial cells through ERK phosphorylation.
Yamato
Masaya
M
Department of Geriatrics and Nephrology, Osaka University School of Medicine, Suita, Japan.
Ishida
Norio
N
Iwatani
Hirotsugu
H
Yamato
Masafumi
M
Rakugi
Hiromi
H
Ito
Takahito
T
D000818:Animals; D001683:Biological Clocks / Q000502:physiology; D002453:Cell Cycle / Q000502:physiology; D018797:Cell Cycle Proteins / Q000378:metabolism; D002460:Cell Line; D002940:Circadian Rhythm / Q000502:physiology*; D004847:Epithelial Cells / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D005247:Feeding Behavior / Q000502:physiology; D055785:Gene Knockdown Techniques; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D007668:Kidney / Q000166:cytology / Q000502:physiology*; D008297:Male; D009687:Nuclear Proteins / Q000378:metabolism; D056950:Period Circadian Proteins; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D018797:Cell Cycle Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; C539024:Per1 protein, rat; C513311:Per2 protein, rat; D056950:Period Circadian Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; C485823:Zfp354a protein, rat; D048049:Extracellular Signal-Regulated MAP Kinases