BRAIN EAGER: Novel Targeting Strategies for Projection-specific Mapping of Neurons

BRAIN EAGER：神经元投影特异性映射的新颖靶向策略

• 批准号: 1547967
• 负责人: Adam Kepecs
• 金额: $ 30万
• 依托单位: Cold Spring Harbor Laboratory
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1547967&HistoricalAwards=false
• 关键词: BRAIN; EAGER; Novel; Targeting; Strategies

A central goal in neuroscience is to understand behavior in terms of the activity and connectivity of specific neurons. Anatomical tracings have revealed the mesoscale connections in the brain, but this dataset lacks functional utility without the ability to behaviorally study neurons with specific connections to other brain regions. Recently, a number of technological advances have enabled these types of experiments, including re-engineered viruses to target specific neuron types and deliver genes of interests. This methodology is important because genetic targeting of specific neurons allows one to draw a link between a neurons's anatomy (the regions it projects to) and its function (the information it encodes). This project will explore the engineering of novel tools that will significantly improve existing retrograde tracing techniques and thereby enable mapping behavioral functions to specific neuron types. The resulting tools will be made broadly available to the community to increase their impact and utility.As systems neuroscience is adopting tools from molecular biology there is an increasing appreciation for the importance of circuit-specific technologies, for instance targeting neuron-types defined by their projections using retrograde viral strategies for anatomical and genetic labeling. These tools have been critical for cell-type specific recordings using genetic activity indicators, or control using optogenetic actuators. Nevertheless, the efficiency and variable tropism (i.e. inability to target all cell types) of existing retrograde viruses presents a challenge for these experimental approaches. To overcome this challenge, two methods are proposed to generate reagents that will provide a non-toxic profile while maximizing efficient labeling of the targeted population. The methods will exploit well-understood molecular mechanisms for viral internalization to overcome tropisms, as well as classic tracers improved using a novel protein ligation technique. These reagents will be suitable for precise and robust anatomical tracing, for induction of opto- and chemicogenetic actuators. Therefore we expect that these improved reagents will allow for more efficient and less variable projection-based targeting of neurons with molecular cargo and facilitate new types of circuit-based mapping experiments.

神经科学的核心目标是了解特定神经元的活动和连通性的行为。解剖示踪揭示了大脑中的中尺度连接，但是该数据集缺乏功能效用，而无需行为与其他大脑区域的特定连接进行行为研究神经元。最近，许多技术进步使这些类型的实验能够进行，包括重新设计的病毒以靶向特定的神经元类型并传递感兴趣的基因。该方法很重要，因为特定神经元的遗传靶向允许人们在神经元的解剖结构（IT投射到的区域）及其功能（其编码的信息）之间建立联系。该项目将探索新型工具的工程，这些工具将显着改善现有的逆行跟踪技术，从而将行为功能映射到特定的神经元类型。所得工具将广泛地向社区提供，以增加其影响和实用性。神经科学正在采用分子生物学的工具，人们对电路特异性技术的重要性的重要性越来越多，例如针对其通过解剖学和遗传标记的逆行病毒策略来定义的神经元类型，例如其投影所定义的神经元类型。这些工具对于使用遗传活性指标或使用光遗传执行器控制的细胞类型记录至关重要。然而，现有的逆行病毒的效率和可变的端主（即无法靶向所有细胞类型）为这些实验方法带来了挑战。为了克服这一挑战，提出了两种方法来产生将提供无毒概况的试剂，同时最大程度地提高目标种群的有效标记。这些方法将利用众所周知的分子机制来克服往流主义，并使用新型的蛋白质连接技术改善了经典的示踪剂。这些试剂将适用于精确和鲁棒的解剖学追踪，用于诱导光和化学遗传致动器。因此，我们预计这些改进的试剂将允许使用分子货物对神经元进行更有效且基于较少的投影靶向，并促进新型的基于电路的映射实验。