Department of Physiology and Biophysics, University of California, Irvine, Irvine, California 92697.
Center for Complex Biological Systems, University of California, Irvine, Irvine, California 92697.
J Neurosci. 2021 Jun 16;41(24):5173-5189. doi: 10.1523/JNEUROSCI.3074-19.2021. Epub 2021 Apr 30.
We developed a method for single-cell resolution longitudinal bioluminescence imaging of PERIOD (PER) protein and TIMELESS (TIM) oscillations in cultured male adult brains that captures circadian circuit-wide cycling under simulated day/night cycles. Light input analysis confirms that CRYPTOCHROME (CRY) is the primary circadian photoreceptor and mediates clock disruption by constant light (LL), and that eye light input is redundant to CRY; 3-h light phase delays (Friday) followed by 3-h light phase advances (Monday morning) simulate the common practice of staying up later at night on weekends, sleeping in later on weekend days then returning to standard schedule Monday morning [weekend light shift (WLS)]. PER and TIM oscillations are highly synchronous across all major circadian neuronal subgroups in unshifted light schedules for 11 d. In contrast, WLS significantly dampens PER oscillator synchrony and rhythmicity in most circadian neurons during and after exposure. Lateral ventral neuron (LNv) oscillations are the first to desynchronize in WLS and the last to resynchronize in WLS. Surprisingly, the dorsal neuron group-3 (DN3s) increase their within-group synchrony in response to WLS. , WLS induces transient defects in sleep stability, learning, and memory that temporally coincide with circuit desynchrony. Our findings suggest that WLS schedules disrupt circuit-wide circadian neuronal oscillator synchrony for much of the week, thus leading to observed behavioral defects in sleep, learning, and memory.
我们开发了一种方法，可以对培养的雄性成年大脑中的 PERIOD（PER）蛋白和 TIMELESS（TIM）振荡进行单细胞分辨率的纵向生物发光成像，从而在模拟的日夜周期下捕获整个生物钟电路的周期性循环。光输入分析证实 CRYPTOCHROME（CRY）是主要的生物钟光感受器，并通过持续光照（LL）介导时钟中断，并且眼睛的光输入对于 CRY 是冗余的；3 小时的光相延迟（星期五），随后是 3 小时的光相提前（星期一早晨），模拟了周末熬夜、周末晚睡晚起然后周一早上恢复正常作息的常见做法[周末光移（WLS）]。在未移位的光时间表中，PER 和 TIM 振荡在所有主要生物钟神经元亚群中高度同步，持续 11 天。相比之下，WLS 在暴露期间和之后显著降低了大多数生物钟神经元中 PER 振荡器的同步性和节律性。外侧腹侧神经元（LNv）振荡是 WLS 中第一个失步的，也是 WLS 中最后一个重新同步的。令人惊讶的是，DN3s 神经元组增加了它们在 WLS 中的组内同步性。此外，WLS 诱导睡眠稳定性、学习和记忆的短暂缺陷，与电路失步时间上一致。我们的发现表明，WLS 时间表破坏了整个生物钟神经元振荡器的同步性，从而导致睡眠、学习和记忆观察到的行为缺陷。
