Howard Hughes Medical Institute, Brandeis University, Waltham MA 02454, USA.
Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.
Sci Adv. 2024 Nov 22;10(47):eads0652. doi: 10.1126/sciadv.ads0652.
Sleep is essential and highly conserved, yet its regulatory mechanisms remain largely unknown. To identify sleep drive neurons, we imaged brains with calcium-modulated photoactivatable ratiometric integrator (CaMPARI). The results indicate that the activity of the protocerebral bridge (PB) correlates with sleep drive. We further identified a key three-layer PB circuit, EPG-SpsP-PEcG, in which the four SpsP neurons in the PB respond to ellipsoid body (EB) signals from EPG neurons and send signals back to the EB through PEcG neurons. This circuit is strengthened by sleep deprivation, indicating a plasticity response to sleep drive. SpsP neurons also receive inputs from the sensorimotor brain region, suggesting that they may encode sleep drive by integrating sensorimotor and navigation cues. Together, our experiments show that the four SpsP neurons and their sleep regulatory circuit play an important and dynamic role in sleep regulation.
睡眠是至关重要且高度保守的，但它的调节机制在很大程度上仍然未知。为了鉴定睡眠驱动神经元，我们使用钙调制的光激活比率积分器（CaMPARI）对大脑进行成像。结果表明，中脑桥脑（PB）的活性与睡眠驱动相关。我们进一步鉴定出一个关键的三层 PB 回路，EPG-SpsP-PEcG，其中 PB 中的四个 SpsP 神经元对来自 EPG 神经元的椭圆体（EB）信号做出反应，并通过 PEcG 神经元将信号发送回 EB。这个回路通过睡眠剥夺而增强，表明这是对睡眠驱动的一种可塑性反应。SpsP 神经元还接收来自感觉运动脑区的输入，表明它们可能通过整合感觉运动和导航线索来编码睡眠驱动。总的来说，我们的实验表明，四个 SpsP 神经元及其睡眠调节回路在睡眠调节中起着重要而动态的作用。
