Postnatal experience shapes gene expression and connectivity development in the cortex

项目摘要 出生后的感觉经验对大脑皮层的成熟、组成和连接有着深远的影响。 细胞类型，但这些变化的系统分析还不可行。这种方法的缺乏， 系统的分析使得很难定义神经活动如何重新连接大脑回路的原理， 连接性的变化是先于还是跟随脑细胞类型的分子变化。系统地 表征来自感觉外周的神经活动如何塑造分子和突触特性， 大脑中的神经回路将受益于新技术，其中突触连接关系和 全基因组RNA可以在体内从相同的单个细胞中测量。高通量，单细胞 解析基因表达和突触连接的方法-包括条形码狂犬病病毒- 基于方法称为幻灯片SBARRO方法在桑德斯实验室开发-非常适合研究如何 感觉输入影响皮层回路的形成。在目标1中，我将使用一种诱导型小鼠模型， 初级听觉皮层（A1）细胞的核RNA测序，以确定听觉输入如何塑造皮层 细胞类型比例和基因表达。在目标2中，我将确定听觉输入如何塑造局部突触， 通过重建数百个空间分辨和细胞类型特异性的单突触， 使用Slide-SBARRO的网络。通过全面描述听觉感觉输入如何改变脑细胞， 和电路特性，这一建议将提高我们的理解的机制， 皮层会对感觉外围的损伤做出反应。最后，这项建议将使我能够开发新的技术 技能和智力的方法，我将用来研究听觉回路可塑性作为一个独立的研究人员。

PROJECT SUMMARY Postnatal sensory experience has a profound effect on the maturation, composition, and connectivity of cortical cell types, but systematic analyses of these changes have not yet been feasible. This lack of methods for systematic analysis had made it difficult to define principles in how neural activity re-wires brain circuits and whether connectivity changes precede or follow molecular changes in brain cell types. Systematically characterizing how neural activity from the sensory periphery shapes the molecular and synaptic properties of neural circuits in the brain would benefit from new technologies in which synaptic connectivity relationships and genome-wide RNAs could be measured in vivo from the same individual cells. High-throughput, single-cell resolved methods to profile gene expression and synaptic connectivity – including the barcoded rabies virus- based method called Slide-SBARRO method developed in the Saunders Lab - are well suited to study how sensory input influences cortical circuit formation. In Aim 1, I will use an inducible mouse model paired with single nucleus RNA sequencing of primary auditory cortex (A1) cells to determine how auditory input shapes cortical cell-type proportions and gene expression. In Aim 2, I will determine how auditory input shapes local synaptic relationships within A1 by reconstructing hundreds of spatially resolved and cell-type-specific monosynaptic networks using Slide-SBARRO. By comprehensively characterizing how auditory sensory input alters brain cell and circuit properties in A1, this proposal will enhance our understanding of the mechanisms through which cortex responds to damage in the sensory periphery. Finally, this proposal will allow me to develop new technical skills and intellectual approaches that I will use to study auditory circuit plasticity as an independent researcher.