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（由应用提供）：光遗传学执行器是可以通过光调节的离子通道或泵，因此可以通过高空间和临时精度打开和关闭神经元活动。光遗传学对恢复盲人患者的视力有很大的希望，但是当前的治疗策略需要应用高强度的蓝绿色光，这构成了残留光损伤的重大风险。因此，对使用短波长光的使用依赖性代表了安全有效实施用于残留疾病的主要障碍。可以通过使用带红移兴奋光谱的光遗传执行器来克服这种障碍。红灯的能量较小，因此对视网膜的破坏也不太损坏。据研究人员认为，研究人员已经感觉到开发了红移的光遗传学执行器，并且通过OPSIN工程在红色转移执行器中取得了很大进展。但是，为了将光遗传性执行器的操作范围扩展到近红外（> 700 nm），需要新的正交方法。本提案的目的是引入一种新型的仿生策略，用于红色转移光遗传执行器：红色移动的发色团取代。这种方法是Opsin Engineering完整的，是基于迁移鱼类使用的策略来实现浑浊水的更好视力的策略。当鲑鱼从开阔的海洋迁移到内陆溪流时（在其中有显着红移）时，它们从使用视网膜作为视觉发色团转变为具有红移光谱特性的4-二羟化遗迹。这种发色团开关引起了鱼类蛋白光谱敏感性的巨大红移，从而增强了动物看到长波长光的能力，从而使动物更深入地凝视着浑浊的流。我们的目标是确定介导视网膜转化为3个4 dodehretrinal的酶，并与体内哺乳动物神经元中的光遗传驱动器共表达，从而红色移动其动作光谱。在特定目标1中，我们在斑马鱼和牛蛙中使用转录组分析来识别介导这种转化的酶，然后在体内表征其功能。在AIM 2中，我们将在体内与红移的光遗传学执行器共表达这种酶，以赋予对近红外光（> 700 nm）的敏感性赋予无功能的小鼠光感受器。这种方法的一个关键特征是，发色团替代可以与在哺乳动物神经系统的任何部分中使用任何现有的执行器的使用。这是该提案有望对光遗传学领域产生宽度影响。