Sigma 1 receptor as a master regulator of pronociceptive protein trafficking in t

描述(申请人提供)：由慢性炎症和神经系统损伤引起的神经性疼痛是目前可用的DRG医疗设备特别难以治疗的，是一个高度棘手的尚未解决的临床问题。开发一种治疗神经病理性疼痛的新方法具有重要意义。许多信号分子可能参与神经病理性疼痛的表现。Sigma 1受体(S1R)是一种主要驻留在内质网的两跨膜蛋白，在基本的细胞过程中发挥着多种作用。S1R基因敲除小鼠最健壮的表型之一是抑制神经病理性疼痛。鞘内给予S1R拮抗剂反映了这种抗神经病理性基因敲除的表型，表明脊髓节段性水平的S1R表达在介导神经病理性疼痛中的重要性。根据S1R在脊髓本身腹角的集中表达，我们认为背根神经节(DRG)中的S1R是关键的作用部位。我们提出了S1R的新概念，作为DRG中前致病蛋白运输的主要调节因子，作为在药物或遗传抑制该蛋白的小鼠中观察到的抗神经病变表型的机制。初步数据证明蛋白质：S1R与几种前伤害性蛋白质之间的相互作用，包括P物质受体(NK1R)、毒扁豆碱M1受体(M1R)和NMDA受体的NR1亚单位，都具有增加细胞内钙信号的能力。S1R的共表达增加了NK1R在这些细胞的质膜表达，从而增加了细胞内钙信号。我们将验证这一极具创新性的工作假说：背根神经节(DRG)中S1R蛋白上调和NK1R、M1R和NMDAR的调节介导神经病理性疼痛。该提案结合了最先进的技术，包括在体选择性转导和击倒背根神经节中的S1R在腺相关病毒2/8，广泛使用共免疫沉淀和新的分子结构来破译负责S1R和客户蛋白之间相互作用的蛋白质结构域，最后研究针对S1R与客户蛋白相互作用的神经病理性疼痛的基因治疗。

DESCRIPTION (provided by applicant): Neuropathic pain resulting from chronic inflammation and injury to the nervous system is particularly difficult to treat with the currently available drg armamentarium and is a highly problematic unsolved clinical problem. Development of a novel treatment for neuropathic pain is highly significant. Many signaling molecules are likely to partake in the manifestation of neuropathic pain. The Sigma 1 receptor (S1R) is a two-transmembrane mostly endoplasmic reticulum resident protein with many roles in fundamental cellular processes. One of the most robust phenotypes described for the S1R knockout mice is the suppression of neuropathic pain. Intrathecal administration of S1R antagonists mirrors this anti-neuropathic phenotype of the knockout indicating the importance of a spinal segmental level expression of S1R in mediating neuropathic pain. Based on the focused expression of S1R in the ventral horn in the spinal cord proper, we believe S1R in the dorsal root ganglion (DRG) is the key anatomical site of action. We propose a novel concept of the S1R as a master regulator of pronocicptive protein trafficking in the DRG as a mechanism underlying the anti- neuropathic phenotype observed in mice with pharmacological or genetic inhibition of this protein. Preliminary data documents protein:protein interaction between S1R and several pronociceptive proteins including the substance P receptor (NK1R), muscarinic M1 receptor (M1R), and the NR1 subunit of the NMDA receptor all sharing the ability to increase intracellular calcium signaling. Co-expression of S1R increases the plasma membrane expression of NK1R in these cells with a consequent increase in intracellular calcium signaling. We will test the highly innovative working hypothesis that: S1R protein upregulation and modulation of NK1R, M1R, and NMDAR in the dorsal root ganglion (DRG) mediates neuropathic pain. The proposal incorporates state-of-art techniques including a selective in vivo transduction and knockdown of S1R in the DRG by adenoassociated virus 2/8, extensive use of co-immunoprecipitation and novel molecular constructs to decipher the protein domains responsible for the interaction between S1R and the client proteins, and finally examines a gene therapy for neuropathic pain targeting S1R interaction with client proteins.