Reference: MicroRNA expression profiling in adult mouse liver following BaP treatment [Agilent miRNA array]. Mus musculus

We have investigated the effect of exposure to 150 mg/kg benzo(a)pyrene (BaP) for 3 days on mRNA and miRNA expression levels in adult mouse liver. We used Agilent miRNA array platforms to assess effects of BaP exposure on miRNA expression levels. Our results indicate a distinct lack of effect of BaP of miRNA expression, despite widespread changes in mRNA levels. The data in the attached array files were used a positive control for the Agilent platform, to indicate that the platform was able to detect significant differences in abundance of miRNA between two samples with great differences in miRNA content. Keywords: Toxicology, miRNA Overall design: Two reference pools were created from commercially available reference RNA (FirstChoice® mouse Total RNA including the small fraction (Catalogue # AM7800-AM7828, Ambion, Streetsville, ON)). Reference #1 contained equal parts of mouse testicle, ovary and 10-12 day embryo. Reference #2 contained liver, heart and lung. These references were hybridized to a single mouse Agilent 8x15K miRNA array (4 replicates each), normalized by cyclic lowess and analysed with MAANOVA to find differences in the samples.One reference #1 sample was not included in the analysis because it did not pass Agilent quality control metrics.

本研究探究了150 mg/kg剂量的苯并(a)芘（benzo(a)pyrene，BaP）暴露3天对成年小鼠肝脏中mRNA和miRNA表达水平的影响。我们采用安捷伦（Agilent）miRNA芯片平台评估BaP暴露对miRNA表达水平的影响。结果显示，尽管mRNA水平发生了广泛的表达变化，但BaP对miRNA表达未产生显著影响。附件中的芯片文件数据被用作安捷伦平台的阳性对照，以证明该平台能够在miRNA含量差异显著的两个样本间检测到miRNA丰度的显著差异。

关键词：毒理学（Toxicology）、miRNA

整体实验设计：
我们从商用参考RNA（FirstChoice®小鼠总RNA，含小RNA组分，货号AM7800-AM7828，安必昂（Ambion），加拿大安大略省斯特里茨维尔）中制备两份参考混合样本。参考样本1由等比例的小鼠睾丸、卵巢及10-12天胚胎的RNA混合制备而成；参考样本2由肝脏、心脏及肺组织的RNA混合制备而成。将两份参考样本分别杂交至单张小鼠安捷伦8x15K miRNA芯片（每个样本设置4次重复），采用循环低ess（cyclic lowess）法进行标准化处理，并通过MAANOVA软件分析样本间的表达差异。其中一份参考样本1的重复样本未纳入本次分析，因其未通过安捷伦的质量控制标准。