DECIPHERING THE MECHANISTIC BASIS OF INFRARED VISION FOR OPTOGENETIC APPLICATIONS

破译红外视觉光遗传学应用的机制基础

基本信息

批准号：
9082683
负责人：
JOSEPH CORBO
金额：
$ 34.31万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-03-01 至 2020-02-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9082683
关键词：
11 cis Retinal Advocate Animals Antibodies Behavioral Assay Biomimetics Brain Carotenoids Cells Coupled Cytochrome P450 Dependence Electrophysiology (science)Engineering Enzymes Eye Family Fishes Genome engineering Goals Human In Vitro Ion Channel Ion Pumps Knock-out Knowledge Light Mammals Mediating Modeling Molecular Molecular Profiling Mus Mutation Nervous system structure Neurons Neurosciences Oceans Opsin Orphan Patients Photophobia Photoreceptors Pigments Production Property Rana catesbeiana Research Personnel Retina Retinal Retinal Diseases Risk Role Salmon Scientist Stream Therapeutic Variant Vision Visual Water Work Zebrafish base blind chromophore clinical application constriction dehydroretinal improved in vivo innovation macula meetings member multi-electrode arrays mutant novel optogenetics peer public health relevance restoration retinal damage retinal neuron success tool transcriptome treatment strategy

项目摘要

DESCRIPTION (provided by applicant): Optogenetic actuators are ion channels or pumps that can be regulated by light, thus permitting neuronal activity to be turned on and off with high spatial and temporal precision. Optogenetics holds significant promise for restoring vision to blind patients, but current treatment strategies require the application of high-intensity blue-green light, which poses a significant risk of retinal photodamage. Dependence on the use of short-wavelength light therefore represents a major barrier to safe and effective implementation of optogenetic therapy for retinal disease. This barrier can be surmounted by the use of optogenetic actuators with red-shifted excitation spectra. Red light is less energetic and therefore less damaging to the retina. Accordingly, researchers have sought to develop red-shifted optogenetic actuators, and considerable progress has been made in red-shifting actuators via opsin engineering. However, in order to extend the operational range of optogenetic actuators into the near-infrared (>700 nm), new orthogonal approaches are needed. The goal of the present proposal is to introduce a novel biomimetic strategy for red-shifting optogenetic actuators: red- shifted chromophore substitution. This approach is complementary to opsin engineering and is based on a strategy used by migrating fish to enable better vision in turbid water. When salmon migrate from the open ocean into inland streams (where incident light is significantly red-shifted), they switch from using retinal as their visual chromophore to , 4-didehydroretinal which has red-shifted spectral properties. This chromophore switch causes a dramatic red-shift of the fish's opsin spectral sensitivity, thereby enhancing the animal's abilityto see long-wavelength light and thus permitting the animal to peer more deeply into turbid streams. Our goal is to identify the enzyme mediating the conversion of retinal into 3, 4-dodehydroretinal, and to co-express it with optogenetic actuators in mammalian neurons in vivo, thereby red-shifting their action spectra. In Specific Aim 1, we use transcriptome profiling in zebrafish and bullfrog to identify the enzyme mediating this conversion, and then characterize its function in vivo. In Aim 2, we will co-express this enzyme with red-shifted optogenetic actuators in vivo to endow non-functioning mouse photoreceptors with sensitivity to near-infrared light (>700 nm). A key feature of this approach is that chromophore substitution can be coupled to the use of any existing actuator in any part of the mammalian nervous system. Thus, this proposal promises to have a widespread impact on the field of optogenetics.

描述（由申请人提供）：光遗传学执行器是可以通过光调节的离子通道或泵，从而允许以高空间和时间精度打开和关闭神经活动，光遗传学对于恢复失明患者的视力具有重大前景。目前的治疗策略需要使用高强度蓝绿光，这会带来视网膜光损伤的重大风险，因此对短波长光的使用的依赖是一个主要因素。安全有效地实施视网膜疾病光遗传学治疗的障碍可以通过使用具有红移激发光谱的光遗传学驱动器来克服，红光能量较低，因此对视网膜的损害较小。开发红移光遗传致动器，并且通过视蛋白工程在红移致动器方面已经取得了相当大的进展，但是为了将光遗传致动器的操作范围扩展到红移致动器。近红外（>700 nm），需要新的正交方法，本提案的目标是引入一种新的红移光遗传学执行器的仿生策略：红移发色团替代，该方法是视蛋白工程的补充。基于迁徙鱼类在浑浊水中获得更好视力所采用的策略。当鲑鱼从公海迁徙到内陆溪流（其中入射光明显红移）时，它们会不再使用光。视网膜作为其视觉发色团转变为具有红移光谱特性的 4-二脱氢视网膜，这种发色团开关导致鱼的视蛋白光谱敏感性发生显着的红移，从而增强动物看到长波长光的能力，从而使动物能够看到。我们的目标是确定介导视黄醛转化为 3, 4-十二氢视黄醛和 3, 4-十二氢视黄醛的酶。在体内与哺乳动物神经元中的光遗传学执行器共表达，从而使它们的作用光谱红移。在特定目标1中，我们使用斑马鱼和牛蛙的转录组分析来鉴定介导这种转换的酶，然后表征其在体内的功能。在目标 2 中，我们将在体内与红移光遗传学执行器共同表达这种酶，以赋予无功能的小鼠光感受器对近红外光的敏感性（>700 nm）该方法的一个关键特征是发色团替换可以与哺乳动物神经系统任何部分中任何现有致动器的使用相结合，因此，该提议有望对光遗传学领域产生广泛的影响。。