神经肽B类G蛋白偶联受体PAC1-R是神经系统药物开发的重要靶点。前期研究发现具有神经系统非抗生素效用的强力霉素靶向PAC1-R的N端胞外域，具有正向别构调节受体的活性；生物信息学分析显示PAC1-RN端胞外域具有显著可识别的别构调节位点。本项目在已有研究的基础上，采用计算机分子对接、定点突变、竞争结合和等温滴定量热法等技术，结合表达PAC1-R的细胞系和PAC1-R相关的记忆损伤和胸腺衰退动物模型，从分子、细胞和动物水平探索强力霉素/米诺环素与类似物别构调节PAC1-R的活性和相关机制；建立一套预测、筛选和鉴定PAC1-R别构调节剂的技术和方案；详尽位于PAC1-R的N端胞外域中别构调节位点的信息；尝试开展针对PAC1-R别构调节位点的小分子调节剂的筛选和鉴定。本项目为强力霉素等非抗生素的 “老药新用”提供药理学支持，也为PAC1-R的新型高效低毒的小分子别构调节剂的发明与创制奠定基础。

Neuropeptide class B G-protein coupled receptor PAC1-R is a key target for the drug development in nervous system. Our previous research revealed for the first time that doxycycline with significant non-antibiotic effects in nervous system targets the N-terminal extracellular domain of PAC1-R, and plays as a positive allosteric modulator. Further bio-information analysis showed that PAC1-R has a discernible allosteric regulation site in its N-terminal extracellular domain. In this project, we aim to 1) identify the targeting and the allosteric regulation effects of doxycycline/minocyline and their analogues on PAC1-R; 2) set up a set of techniques and methods for the screening and characterization of the allosteric modulators of PAC1-R; 3) clarify the information of the allosteric regulation site located in the N-terminal extracellular domain of PAC1-R and 4) try to screen and characterize the novel small molecular allosteric modulators of PAC1-R. The research methods including computer molecular docking, site-mutation, competition binding assays, isothermal titration calorimetry and so on, are to be used in this project, combined with some cell lines with expression of PAC1-R and the PAC1-R related animal models of amnesia and of thymus recession. This research will not only offer the pharmacological support for the conventional drugs of doxycyline and its analogues in the non-antibiotic new use, but also promote the finding and the innovation of novel effective non-toxic small molecular allosteric modulators targeting PAC1-R.