Gene expression analysis of mouse brain.

Inbred mouse strains differ in their innate anxiety levels. We used RNA-sequencing to identify gene expression differences in hippocampus and frontal cortex of six mouse strains. Mice were singly housed for one week before dissections and killed by cervical dislocation between 8 a.m. and 11 a.m. Dissections were performed on a Petri dish filled with ice. FCx included 2 mm of the anterior part of the cortex. The Hpc was dissected whole. Samples were directly frozen in liquid nitrogen and stored in -80°C. We extracted total RNA with TriReagent according to the manufacturer's instructions and verified its quality by the Agilent Bioanalyzer Small RNA Analysis and RNA 6000 Nano Kits. Ribo-depleted RNA was sequenced with Illumina High-Seq 2000.近交系小鼠品系的先天性焦虑水平存在差异。我们采用RNA测序（RNA-sequencing）技术，对6个小鼠品系的海马体（Hpc）与前额叶皮层（FCx）的基因表达差异进行鉴定。实验小鼠在解剖前单笼饲养一周，于上午8时至11时之间通过颈椎脱臼法处死。解剖操作在装满冰的培养皿中进行：前额叶皮层（FCx）取材于皮层前部2mm区域，海马体（Hpc）则进行完整取材。样本经液氮直接速冻后，保存于-80℃环境中。我们按照生产商说明书，使用TriReagent试剂提取总RNA，并通过安捷伦生物分析仪的Small RNA Analysis与RNA 6000 Nano试剂盒对RNA质量进行验证。采用Illumina High-Seq 2000测序平台对经核糖体RNA去除处理的RNA样本进行测序。