Abstract:
Orexin neuropeptides carry out important neuromodulatory functions in the brain, yet tools to precisely control the activation of endogenous orexin signaling are lacking. Here, we developed a photocaged orexin-B (photo-OXB) through a C-terminal photocaging strategy. We show that photo-OXB is unable to activate its cognate receptors in the dark but releases functionally active native orexin-B upon uncaging by illumination with UV-visible (UV-vis) light (370-405 nm). We established an all-optical assay combining photo-OXB with a genetically encoded orexin biosensor and used it to characterize the efficiency and spatial profile of photo-OXB uncaging. Finally, we demonstrated that photo-OXB enables optical control over orexin signaling with fine temporal precision both in vitro and ex vivo. Thus, our photocaging strategy and photo-OXB advance the chemical biological toolkit by introducing a method for the optical control of peptide signaling and physiological function.
摘要:
Orexin神经肽在大脑中执行重要的神经调节功能,然而,缺乏精确控制内源性食欲素信号激活的工具。这里,我们通过C端光老化策略开发了光老化的食欲素B(photo-OXB)。我们表明,photo-OXB无法在黑暗中激活其同源受体,但在用UV-可见光(UV-vis)光(370-405nm)照射时释放功能活性的天然食欲素B。我们建立了一种将photo-OXB与基因编码的orexin生物传感器相结合的全光学测定法,并用它来表征photo-OXB解套的效率和空间分布。最后,我们证明了光-OXB能够在体外和体外以良好的时间精度对食欲素信号进行光学控制。因此,我们的光老化策略和photo-OXB通过引入肽信号和生理功能的光学控制方法来推进化学生物工具包。