Sentrin proteases, CRMP2 deSUMOylation, and Chronic Pain

Sentrin 蛋白酶、CRMP2 去SUMO化和慢性疼痛

• 批准号: 10253377
• 负责人: Rajesh Khanna
• 金额: $ 19.89万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-15 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10253377
• 关键词: Action Potentials; Address; Affect; Afferent Neurons; Axon; Behavior assessment; Biochemical Pathway; Biological Assay; Biological Process; Cell membrane; Cells; Clathrin; Clustered Regularly Interspaced Short Palindromic Repeats; Cognitive; Complement; Confocal Microscopy; Development; Electrophysiology (science); Endocytosis; Enzymes; Equilibrium; Etiology; Evaluation; Excision; Functional disorder; Gene Expression; Generations; Genetic; Genetic Transcription; Human; Immunoblotting; Injury; Intrathecal Injections; Ion Channel; Knowledge; Ligation; Lysine; Maintenance; Mechanics; Mediating; Membrane; Methods; Modification; Motivation; Mus; Neurons; Nociception; Outcome; Pain; Pathologic; Peptide Hydrolases; Pharmacology; Phosphoproteins; Phosphorylation; Play; Post-Translational Protein Processing; Process; Proteins; Rattus; Reflex action; Regulation; Reporting; Resistance; Rodent; Rodent Model; Role; SCN2A protein; Small Ubiquitin-Related Modifier Proteins; Sodium Channel; Spinal Cord; Spinal Ganglia; Stimulus; Sumoylation Pathway; Surface; Testing; Therapeutic; Thermal Hyperalgesias; Transfection; Transgenic Organisms; Translating; Ubiquitin; Variant; Work; axon guidance; chronic neuropathic pain; chronic pain; collapsin response mediator protein-2; density; design; improved; interest; mechanical allodynia; mutant; neuronal excitability; neurotransmission; novel therapeutic intervention; overexpression; pain behavior; pain relief; pain signal; painful neuropathy; pleiotropism; prevent; protein protein interaction; skills; small molecule; sulfoenolpyruvate; trafficking; voltage

ABSTRACT Chronic pain is a pathological state where sensory neurons become hyperexcitable leading to nociceptive neurotransmission in the absence of a painful stimulus. Genetic and functional studies have established the voltage-gated sodium channel Nav1.7 as a major contributor to human pain signaling. Alterations of the trafficking of Nav1.7 appears to be a central mechanism in the etiology of neuropathic pain. Although the dysregulation of Nav1.7 is poorly understood, it is thought to involve mechanisms related to surface trafficking and regulation via protein-protein interactions. Membrane trafficking and functional activity of Nav1.7 is under the control of the axonal collapsin response mediator protein 2 (CRMP2). While CRMP2 can regulate a pleiotropy of functions, regulation of Nav1.7 is specifically guided by small ubiquitin-like modifier (SUMO)ylation. SUMOylation is a dynamic and reversible posttranslational modification of lysine residues in target proteins by SUMOs. CRMP2 SUMOylation relies on its prior phosphorylation by Cdk5. Phosphorylated CRMP2 can also regulate other ion channels such as CaV2.2 but its SUMOylation is exclusive for Nav1.7. In chronic neuropathic pain, increased CRMP2 SUMOylation correlates with enhanced Nav1.7 function. Genetic interference of CRMP2 SUMOylation via expression of a SUMO-null CRMP2 mutant (K374A) in rats with neuropathic pain was sufficient to reverse mechanical allodynia. Similarly, in CRMP2K374A/K374A mice, where CRMP2 SUMOylation is abolished, Nav1.7 currents, trafficking and interaction with CRMP2 were reduced in the dorsal root ganglia (DRG). These mice showed resistance to the development of mechanical allodynia after a neuropathic pain injury. To study in more details the role of CRMP2 SUMOylation in chronic neuropathic pain, I got interested in the sentrin/SUMO- specific protease (SENPs) that catalyze the deSUMOylation of proteins. Interestingly, increasing deSUMOylation with overexpression of sentrin/SUMO-specific protease SENP1 and/or SENP2 CRMP2-expressing heterologous cells decreases surface Nav1.7 expression and currents. Although SUMO-1 and SENP1 are expressed in the spinal cord and in DRG neurons their roles in Nav1.7 function and pain as never been investigated. Most of the past work focused on studying the effects of CRMP2 SUMOylation; there is only limited evidence regarding the study of this modification in reverse. Therefore, our overall hypothesis is that by enhancing CRMP2 deSUMOylation by SENP1 can, in turn, control Nav1.7-dependent DRG neuron excitability and contribute to initiation and maintenance of chronic neuropathic pain.

摘要 慢性疼痛是一种病理状态，其中感觉神经元变得过度兴奋，导致伤害性疼痛。 在没有疼痛刺激的情况下神经传递。遗传和功能研究已经建立了 电压门控钠通道Nav1.7作为人类疼痛信号传导的主要贡献者。的改变 Nav1.7的运输似乎是神经性疼痛病因学中的中心机制。虽然 Nav1.7的调节异常知之甚少，它被认为涉及与表面运输相关的机制， 和通过蛋白质-蛋白质相互作用的调节。Nav1.7的膜运输和功能活性受到抑制。 轴突再生素反应介导蛋白2（CRMP 2）的控制。虽然CRMP 2可以调节多效性， Nav1.7的调控受小泛素样修饰物（SUMO）化的特异性指导。 SUMO化是靶蛋白中赖氨酸残基的动态和可逆的翻译后修饰， 相扑CRMP 2 SUMO化依赖于其先前被Cdk 5磷酸化。磷酸化CRMP 2也可以 调节其他离子通道，如CaV2.2，但其SUMO化是Nav1.7独有的。在慢性神经病 疼痛，CRMP 2 SUMO化增加与Nav1.7功能增强相关。CRMP 2的遗传干扰 在神经病理性疼痛大鼠中，通过表达SUMO无效CRMP 2突变体（K374 A）的SUMO化是足够的 来逆转机械性痛觉超敏类似地，在CRMP 2K 374 A/K374 A小鼠中，其中CRMP 2 SUMO化被消除， Nav1.7电流、运输和与CRMP 2的相互作用在背根神经节（DRG）中减少。这些 小鼠在神经病理性疼痛损伤后显示出对机械异常性疼痛发展的抵抗力。留学 更详细的CRMP 2 SUMO化在慢性神经性疼痛中的作用，我对sentrin/SUMO产生了兴趣， 催化蛋白质去SUMO化的特异性蛋白酶（SENP）。有趣的是， 过表达sentrin/SUMO特异性蛋白酶SENP 1和/或SENP 2 CRMP 2的异源 细胞表面Nav1.7表达和电流降低。尽管SUMO-1和SENP 1在哺乳动物中表达， 在脊髓和DRG神经元中，它们在Nav1.7功能和疼痛中的作用从未被研究过。大部分 过去的工作集中在研究CRMP 2 SUMO化的影响;关于CRMP 2 SUMO化的影响，只有有限的证据。 研究这种反向的修改。因此，我们的总体假设是，通过增强CRMP 2 SENP 1的去SUMO化反过来可以控制Nav1.7依赖性DRG神经元兴奋性，并有助于 慢性神经性疼痛的起始和维持。