Optogenetic Targeting of mGluR5 Receptor Signaling

mGluR5 受体信号转导的光遗传学靶向

• 批准号: 8724139
• 负责人: M. FOSTER OLIVE
• 金额: $ 19.29万
• 依托单位: ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8724139
• 关键词: Acute; Agonist; Alzheimer' s Disease; Animal Model; Behavior; Behavioral; Behavioral Paradigm; Biochemical; Brain; Brain region; C-terminal; Calmodulin; Carybdea; Cattle; Cerebral cortex; Chemosensitization; Chimeric Proteins; Cognitive; Cubozoa; Development; Disease; Drug Addiction; Extracellular Domain; Fragile X Syndrome; Genetic; Glutamates; Goals; Health; Image; Imagery; Impaired cognition; Intake; Investigation; Laboratories; Lead; Legal; Lentivirus Vector; Light; Mediating; Mediator of activation protein; Medical; Methamphetamine; N-Methyl-D-Aspartate Receptors; Neurons; Opsin; Optics; Pharmaceutical Preparations; Phosphotransferases; Photobleaching; Play; Property; Protein Isoforms; Proteins; Psychological reinforcement; Rattus; Receptor Activation; Receptor Signaling; Relapse; Reporter; Research; Resistance; Retinal; Retinaldehyde; Reversal Learning; Rhodopsin; Rodent Model; Role; Schizophrenia; Self Administration; Signal Transduction; Societies; Specificity; Subfamily lentivirinae; Substance Use Disorder; Time; Transmembrane Domain; Viral; addiction; cell type; cost; drug reward; improved; in vivo; insight; learning extinction; memory recognition; metabotropic glutamate receptor 5; neuropsychiatry; novel; novel therapeutics; object recognition; optogenetics; promoter; receptor; receptor function; selective expression; socioeconomics; spatiotemporal; tool; vector

DESCRIPTION (provided by applicant): The type 5 metabotropic glutamate receptor (mGluR5) plays a critical role in various aspects of drug addiction. Pharmacological or genetic inactivation of mGluR5 receptors reduces drug reward, reinforcement, and relapse- like behaviors. On the other hand, pharmacological potentiation of mGluR5 function via positive allosteric modulators (PAMs) produces pro-cognitive effects such as facilitated extinction learning and reversal of drug- induced cognitive impairments. However, various challenges and limitations to pharmacological activation of mGluR5 receptors significantly limit its utility as a research tool for detailed investigation of mGluR5 function in drug addiction. Such limitations include poor spatiotemporal control and lack of cell-type specificity of receptor activation, non-selectivity of orthosteric mGluR5 agonists, and suboptimal physiochemical properties of mGluR5 PAMs. These technical limitations can be surmounted by the successful development of optogenetic tools that allow for precise spatiotemporal and cell-type specific activation of mGluR5 receptor signaling. We have recently developed and performed a preliminary characterization of a lentiviral vector that expresses light- activated mGluR5 receptor (OptoXR-mGluR5). The expression of OptoXR-mGluR5 is under the control of Ca2+/calmodulin-dependent kinase IIα (CaMKIIα) promoter, allowing for selective expression in cortical glutamatergic neurons, and the vector also encodes enhanced yellow fluorescent protein (eYFP) reporter protein for visualization of expression. Our preliminary characterization of this lentivirus in the rat cerebral cortex in vivo demonstrates its cell-type specificity and ability to acutely activate mGluR5 signaling. However, the effects of OptoXR-mGluR5 activation in animal models of addiction-related behaviors and cognitive dysfunction have not yet been assessed. In addition, the ability of repeated stimulation of OptoXR-mGluR5 to consistently activate mGluR5 signaling, which would be necessary for behavioral studies conducted over the course of days or weeks, has not yet been explored. Therefore, the overarching goals of the studies proposed in this application are to examine the behavioral effects of acute OptoXR-mGluR5 activation in a rodent model of drug-induced cognitive dysfunction, and to develop novel tools for optogenetic activation of mGluR5 signaling that are amenable to behavioral paradigms involving repeated stimulation. These goals will be achieved under two independent Specific Aims. In Specific Aim 1, we will assess the ability of acute activation of OptoXR-mGluR5 to reverse drug-induced cognitive dysfunction. In Specific Aim 2, we will develop novel optogenetic tools for repeated activation of mGluR5 signaling. Successful development of optogenetic tools for mGluR5 activation will allow for an unprecedented level of investigation into the role of these receptors n various aspects of drug addiction. Optogenetic tools for mGluR5 activation may also provide insight into pathophysiological mechanisms and novel therapeutic avenues for other neuropsychiatric disorders in which mGluR5 receptors are implicated, including Alzheimer's disease, Fragile X syndrome, and schizophrenia.

描述(申请人提供)：5型代谢性谷氨酸受体(MGluR5)在药物成瘾的各个方面发挥关键作用。MGluR5受体的药理或遗传失活减少了药物奖励、强化和复发行为。另一方面，通过正变构调节剂(PAM)对mGluR5功能的药理增强可以产生促进消失性学习和逆转药物引起的认知障碍等前认知效应。然而，对mGluR5受体药理激活的各种挑战和限制大大限制了其作为详细研究mGluR5在药物成瘾中作用的研究工具的实用性。这些限制包括较差的时空控制和缺乏受体激活的细胞类型特异性，邻位mGluR5激动剂的非选择性，以及mGluR5 PAM的次优物理化学性质。光遗传学工具的成功开发可以克服这些技术限制，这种工具允许mGluR5受体信号的精确时空和细胞类型特异性激活。我们最近开发了一种表达光激活mGluR5受体(OptoXR-mGluR5)的慢病毒载体并进行了初步鉴定。OptoXR-mGluR5的表达受钙/钙调蛋白依赖的激酶IIα(CaMKIIα)启动子的控制，允许在皮质谷氨酸能神经元中选择性表达，并编码增强型黄色荧光蛋白报告蛋白用于表达的可视化。我们在活体大鼠大脑皮层中对这种慢病毒的初步鉴定表明了它的细胞类型特异性和能力 尖锐地激活mGluR5信号。然而，在成瘾相关行为和认知功能障碍的动物模型中，OptoXR-mGluR5激活的影响尚未得到评估。此外，重复刺激OptoXR-mGluR5以持续激活mGluR5信号的能力尚未被探索，这是进行几天或几周的行为研究所必需的。因此，本申请中提出的研究的总体目标是在药物诱导的认知功能障碍的啮齿动物模型中检测OptoXR-mGluR5的急性激活对行为的影响，并开发新的工具来光基因激活mGluR5信号，该工具服从涉及重复刺激的行为范式。这些目标将在两个独立的具体目标下实现。在具体目标1中，我们将评估急性激活OptoXR-mGluR5逆转药物诱导的认知功能障碍的能力。在具体目标2中，我们将开发用于重复激活mGluR5信号的新型光遗传学工具。MGluR5激活的光遗传工具的成功开发将使对这些受体在药物成瘾的各个方面的作用的研究达到前所未有的水平。MGluR5激活的光遗传学工具也可能为其他与mGluR5受体相关的神经精神疾病提供深入的病理生理机制和新的治疗途径，包括阿尔茨海默病、脆性X综合征和精神分裂症。