Schmidt Eric F, Kus Laura, Gong Shiaoching, Heintz Nathaniel
Cold Spring Harb Protoc. 2013 Mar 1;2013(3):pdb.top073692. doi: 10.1101/pdb.top073692.
The brain is a complex tissue comprising hundreds of distinct cell types, each of which has unique circuitry and plays a discrete role in nervous system function. Large-scale studies mapping gene-expression patterns throughout the nervous system have revealed that many genes are exclusively expressed in specific cell populations. The GENSAT (Gene Expression Nervous System Atlas) Project created a library of engineered mice utilizing bacterial artificial chromosomes (BACs) to drive the expression of enhanced green fluorescent protein (eGFP) in genetically defined cell populations. BACs contain large segments of genomic DNA and retain most of the transcriptional regulatory elements directing the expression of a given gene, resulting in more faithful reproduction of endogenous expression patterns. BAC transgenic mice offer a robust solution to the challenging task of stably and reproducibly accessing specific cell types from a heterogeneous tissue such as the brain. A significant advantage of utilizing eGFP as a reporter is the fact that it can fill entire cells, including neuronal dendrites and axons as well as glial processes, making GENSAT reporter mice a powerful tool for neuroimaging studies. This article provides a primer on the generation of BAC transgenic mice and advantages for their use in labeling genetically defined cell types. It also provides an overview of searching the GENSAT database and ordering engineered mouse lines.
大脑是一种复杂的组织，由数百种不同的细胞类型组成，每种细胞类型都有独特的神经回路，并在神经系统功能中发挥着不同的作用。在整个神经系统中绘制基因表达模式的大规模研究表明，许多基因仅在特定的细胞群体中表达。基因表达神经系统图谱（GENSAT）项目利用细菌人工染色体（BAC）创建了一个工程小鼠文库，以驱动增强型绿色荧光蛋白（eGFP）在基因定义的细胞群体中表达。BAC包含大片段的基因组DNA，并保留了指导给定基因表达的大部分转录调控元件，从而更忠实地再现内源性表达模式。BAC转基因小鼠为从大脑等异质组织中稳定且可重复地获取特定细胞类型这一具有挑战性的任务提供了一个有力的解决方案。利用eGFP作为报告基因的一个显著优点是，它可以填充整个细胞，包括神经元的树突和轴突以及胶质细胞的突起，这使得GENSAT报告基因小鼠成为神经影像学研究的有力工具。本文提供了关于BAC转基因小鼠的产生及其用于标记基因定义的细胞类型的优势的入门知识。它还概述了搜索GENSAT数据库和订购工程小鼠品系的方法。
