FIG 4.

The oscillation of other clock genes regulated by Dbp was sustained by the poly(C) motif within the Dbp promoter. (A) Dbp, Cry1, Bmal1, Per2, Rev-erbα, and Rorβ mRNA oscillation levels were quantified. The oscillation levels of Cry1 and Bmal1 mRNAs were slightly affected by Dbp knockdown; however, Per2, Rev-erbα, and Rorβ mRNA oscillation levels were disrupted by Dbp knockdown (n = 3). The error bars indicate SEM. (B) The mRNA oscillation amplitude of Dbp was decreased when its poly(C) motif was deleted. However, Cry1 and Bmal1 mRNA oscillation levels were only slightly changed. Interestingly, the oscillation levels of Per2, Rev-erbα, and Rorβ mRNAs were disrupted due to the deletion of the poly(C) motif within the Dbp promoter (n = 3). The error bars indicate SEM. (C) Our suggested model of regulation by the poly(C) motif is illustrated with Dbp, which regulates other Dbp-controlled genes. The asterisks mark the position of the poly(C) motif.