Restricted feeding induces daily expression of clock genes and Pai-1 mRNA in the heart of Clock mutant mice.
Plasminogen activator inhibitor-1 (PAI-1) is a key factor of fibrinolytic activity. The activity and mRNA abundance show a daily rhythm. To elucidate the mechanism of daily Pai-1 gene expression, the expression of Pai-1 and several clock genes was examined in the heart of homozygous Clock mutant (Clock/Clock) mice. Damping of the daily oscillation of Pai-1 gene expression in Clock/Clock mice was accompanied with damped or attenuated oscillations of mPer1, mPer2, mBmal1, and mNpas2 mRNA. Daily restricted feeding induced a daily mRNA rhythm of all clock genes and Pai-1 mRNA in Clock/Clock mice as well as wild-type mice. The peaks of clock genes and Pai-1 mRNA were phase-advanced in the heart of both genotypes after 6 days of restricted feeding. The present results demonstrate that daily Pai-1 gene expression depends on clock gene expression in the heart and that a functional Clock gene is not required for restricted feeding-induced resetting of the peripheral clock.
Department of Pharmacology and Brain Science, School of Human Sciences, Waseda University, Tokorozawa, Saitama 359-1192, Japan.
Yoichi
Y
Minami
Kazumasa
K
Horikawa
Masashi
M
Akiyama
Shigenobu
S
Shibata
D000818:Animals; D001483:Base Sequence; D056926:CLOCK Proteins; D002940:Circadian Rhythm / Q000235:genetics*; D017931:DNA Primers; D004038:Diet, Reducing; D004435:Eating / Q000502:physiology*; D005786:Gene Expression Regulation / Q000502:physiology; D006321:Heart / Q000502:physiology*; D008029:Lighting; D051379:Mice; D008817:Mice, Mutant Strains; D016601:RNA-Binding Proteins / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015534:Trans-Activators / Q000235:genetics*
D017931:DNA Primers; D016601:RNA-Binding Proteins; C428129:SERBP1 protein, human; D015534:Trans-Activators; D056926:CLOCK Proteins; C538943:CLOCK protein, human; C538944:Clock protein, mouse