PMC

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.

Attenuated gamma band oscillation by optogenetic suppression of PV-IN sustained activity. A, Left, Example traces showing the effect of green laser stimulation on LFP oscillation in the hippocampus of a PV^GFP mouse. The theta (5–12 Hz) and gamma band (35–85 Hz) filtered activities from a representative LFP are shown in black traces. Note increased amplitude in gamma band oscillation after the CS onset. Right, Example traces showing the effect of PV-IN sustained activity suppression on LFP oscillation in the hippocampus of a PV^ArchT mouse. The theta (5–12 Hz) and gamma band (35–85 Hz) filtered activities from a representative LFP were shown in red traces. CS, blue bar; US, gray bar. Calibration: 0.5 mV for LFP amplitude or 100 ms for time. Bi–iii, Average LFP power spectra (i) from the PV^ArchT (n =7, pink) and PV^GFP (n =7, black) mice during the CS-US interval period. The change of gamma band (35–85 Hz) oscillation during the CS-US interval period in PV^ArchT mice (n = 7, pink, ii) and PV^GFP (n = 7, black) mice (iii). The change of theta band (5–12 Hz) oscillation during the CS-US interval period in PV^ArchT mice (n = 7, pink) and PV^GFP (n = 7, black) mice. Ci–iii, Average LFP power spectra from the PV^ArchT (n =7, pink, i) and PV^GFP (n =7, black) mice during the US period (i). The change of gamma band (35–85 Hz) oscillation during the US period in PV^ArchT mice (n = 7, pink) and PV^GFP (n = 7, black) mice (ii). The change of theta band (5–12 Hz) oscillation during the US period in PV^ArchT mice (n = 7, pink) and PV^GFP (n = 7, black) mice (iii). Bi, Ci, Shading represents SEM. Bii,iii, Cii,iii, Box plots show median ± IQR, whiskers show range. *p < 0.01, n.s. p > 0.05.

Dependence of Ca²⁺ oscillation frequency on C_MCU and C_IP3R. (A) Heatmap of oscillation frequency as a function of C_MCU and [IP₃]. At low [IP₃] (corresponding to region α, the µd-dominant region), oscillations were present only at select values of C_MCU. At higher [IP₃] (corresponding to region β, the Cyt-dominant region), the oscillation frequency remained almost unchanged with respect to C_MCU. (B) Clamping of J_IP3R resulted in loss of oscillatory activity in the Cyt-dominant region, but sustained activity in the µd-dominant region. (C) Clamping of J_IP3Rµd resulted in loss of oscillations in the µd-dominant region, but activity was sustained in the Cyt-dominant region. (D,E) Oscillation frequency was computed as a function of C_MCU and C_IP3R at two [IP₃]. (D) In region α, the highest oscillation frequency occurred with C_MCU close to 1 and C_IP3R of ~0.5. Higher values of C_IP3R resulted in loss of oscillations. (E) In region β, the oscillation frequency remained almost unchanged with respect to C_MCU, but oscillations were lost at C_IP3R > ~0.6.

A. A comparison of the solutions of Eq. (17) with different time delay (–15 and –20, respectively) under the same condition of , and . No sustained oscillations occur in both cases. B. Under the same condition of , and , the solution of Eq. (17) with indicates a damped oscillation on the way to steady state, while the case with corresponds to sustained oscillation. C. Plots of the synthesis rate (without delay), the degradation rate and the rate of synthesis containing delay, against the present value . The blue curve indicates the damped oscillation. D. Plots of the synthesis rate (without delay), the degradation rate and the rate of synthesis containing delay, against the present value . The blue circle indicates sustained oscillation.