Transcriptional program of Kpna2/Importin-α2 regulates cellular differentiation-coupled circadian clock development in mammalian cells.
The circadian clock in mammalian cells is cell-autonomously generated during the cellular differentiation process, but the underlying mechanisms are not understood. Here we show that perturbation of the transcriptional program by constitutive expression of transcription factor c-Myc and DNA methyltransferase 1 (Dnmt1) ablation disrupts the differentiation-coupled emergence of the clock from mouse ESCs. Using these model ESCs, 484 genes are identified by global gene expression analysis as factors correlated with differentiation-coupled circadian clock development. Among them, we find the misregulation of Kpna2 (Importin-α2) during the differentiation of the c-Myc-overexpressed and Dnmt1(-/-) ESCs, in which sustained cytoplasmic accumulation of PER proteins is observed. Moreover, constitutive expression of Kpna2 during the differentiation culture of ESCs significantly impairs clock development, and KPNA2 facilitates cytoplasmic localization of PER1/2. These results suggest that the programmed gene expression network regulates the differentiation-coupled circadian clock development in mammalian cells, at least in part via posttranscriptional regulation of clock proteins.
Department of Physiology and Systems Bioscience, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan;
Yasuhiro
Y
Umemura
Department of Physiology and Systems Bioscience, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan;
Nobuya
N
Koike
Department of Physiology and Systems Bioscience, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan;
Tsuguhiro
T
Matsumoto
Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030;
Seung-Hee
SH
Yoo
Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030;
Zheng
Z
Chen
Department of Biochemistry, Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan;
Noriko
N
Yasuhara
Department of Neuroscience and Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390; and Joseph.Takahashi@UTSouthwestern.edu kyagita@koto.kpu-m.ac.jp.
Joseph S
JS
Takahashi
Department of Physiology and Systems Bioscience, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan; Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan Joseph.Takahashi@UTSouthwestern.edu kyagita@koto.kpu-m.ac.jp.
Kazuhiro
K
Yagita
D000818:Animals; D002454:Cell Differentiation / Q000502:physiology*; D057906:Circadian Clocks; D053595:Embryonic Stem Cells / Q000166:cytology; D044127:Epigenesis, Genetic; D051379:Mice; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic; D028901:alpha Karyopherins
C490631:Kpna2 protein, mouse; D009687:Nuclear Proteins; D028901:alpha Karyopherins
Dnmt1; Kpna2 (Importin-α2); c-Myc; cellular differentiation; circadian clock