Effects of fasting and re-feeding on the expression of Dec1, Per1, and other clock-related genes.
To elucidate the food-entrainable oscillatory mechanism of peripheral clock systems, we examined the effect of fasting on circadian expression of clock genes including Dec1 and Dec2 in mice. Withholding of food for 2 days had these effects: the expression level of Dec1 mRNA decreased in all tissues examined, although Per1 mRNA level markedly increased; Per2 expression was reduced in the liver and heart only 42-46 h after the start of fasting; and expression profiles of Dec2 and Bmal1 were altered only in the heart and in the liver, respectively, whereas Rev-erbalpha mRNA levels did not change significantly. Re-feeding after 36-h starvation erased, at least in part, the effect of fasting on Dec1, Dec2, Per1, Per2, and Bmal1 within several hours, and restriction feeding shifted the phase of expression profiles of all examined clock genes including Dec1 and Dec2. These findings indicate that short-term fasting and re-feeding modulate the circadian rhythms of clock genes to different extents in peripheral tissues, and suggest that the expression of Dec1, Per1, and some other clock genes was closely linked with the metabolic activity of these tissues.
Kawamoto
Takeshi
T
Department of Dental and Medical Biochemistry and Department of Prosthetic Dentistry, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima 734-8553.
Noshiro
Mitsuhide
M
Furukawa
Masae
M
Honda
Kiyomasa K
KK
Nakashima
Ayumu
A
Ueshima
Taichi
T
Usui
Emiko
E
Katsura
Yuki
Y
Fujimoto
Katsumi
K
Honma
Sato
S
Honma
Ken-ichi
K
Hamada
Taizo
T
Kato
Yukio
Y
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism*; D001683:Biological Clocks / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002940:Circadian Rhythm / Q000502:physiology*; D005215:Fasting / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D018398:Homeodomain Proteins / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009206:Myocardium / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D056950:Period Circadian Proteins; D013997:Time Factors
D051792:Basic Helix-Loop-Helix Proteins; D018797:Cell Cycle Proteins; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; D056950:Period Circadian Proteins; C491539:Bhlhe40 protein, mouse; C539023:Per1 protein, mouse