TY - JOUR
T1 - SCFβ-TRCP controls Clock-dependent transcription via casein kinase 1-dependent degradation of the mammalian period-1 (Per1) protein
AU - Shirogane, Takahiro
AU - Jin, Jianping
AU - Ang, Xiaolu L.
AU - Harper, J. Wade
PY - 2005/7/22
Y1 - 2005/7/22
N2 - Circadian rhythms are controlled by the periodic accumulation of Period proteins, which act as transcriptional repressors of Clock-dependent genes. Period genes are themselves Clock targets, thereby establishing a negative transcriptional feedback circuit controlling circadian periodicity. Previous data have implicated the CK1ε isolog Doubletime (Dbt) and the F-box protein Slimb in the regulation of Drosophila Period (Per) through an unknown mechanism. In this work, we have identified components of the machinery involved in regulating the abundance of human Per1 in tissue culture cells. CK1ε and CK1γ2 were found to bind to Per1 and to promote its degradation in an in vivo deg-radation assay. Per1 turnover was blocked by a dominant negative version of the Cul1 protein, a component of the SCF (Skp1-Cul1-F-box protein) ubiquitin ligase. We screened a panel of F-box proteins for those that would associate with Per1 in a CK1ε-dependent manner, and we identified β-TRCP1 and β-TRCP2, isologs of the Drosophila Slimb protein. RNA interference against β-transducin repeat-containing protein (β-TRCP) stabilizes endogenous and exogenous Per1. β-TRCP associates with sequences near the N terminus of Per1 in a region distinct from the previously characterized CK1ε-binding site. β-TRCP and CK1ε promote Per1 ubiquitination in vitro. Finally, RNA interference against β-TRCP greatly decreases Clock-dependent gene expression in tissue culture cells, indicating that β-TRCP controls endogenous Per1 activity and the circadian clock by directly targeting Per1 for degradation.
AB - Circadian rhythms are controlled by the periodic accumulation of Period proteins, which act as transcriptional repressors of Clock-dependent genes. Period genes are themselves Clock targets, thereby establishing a negative transcriptional feedback circuit controlling circadian periodicity. Previous data have implicated the CK1ε isolog Doubletime (Dbt) and the F-box protein Slimb in the regulation of Drosophila Period (Per) through an unknown mechanism. In this work, we have identified components of the machinery involved in regulating the abundance of human Per1 in tissue culture cells. CK1ε and CK1γ2 were found to bind to Per1 and to promote its degradation in an in vivo deg-radation assay. Per1 turnover was blocked by a dominant negative version of the Cul1 protein, a component of the SCF (Skp1-Cul1-F-box protein) ubiquitin ligase. We screened a panel of F-box proteins for those that would associate with Per1 in a CK1ε-dependent manner, and we identified β-TRCP1 and β-TRCP2, isologs of the Drosophila Slimb protein. RNA interference against β-transducin repeat-containing protein (β-TRCP) stabilizes endogenous and exogenous Per1. β-TRCP associates with sequences near the N terminus of Per1 in a region distinct from the previously characterized CK1ε-binding site. β-TRCP and CK1ε promote Per1 ubiquitination in vitro. Finally, RNA interference against β-TRCP greatly decreases Clock-dependent gene expression in tissue culture cells, indicating that β-TRCP controls endogenous Per1 activity and the circadian clock by directly targeting Per1 for degradation.
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U2 - 10.1074/jbc.M502862200
DO - 10.1074/jbc.M502862200
M3 - Article
C2 - 15917222
AN - SCOPUS:22844432019
SN - 0021-9258
VL - 280
SP - 26863
EP - 26872
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 29
ER -