Gene expression from splenic cells in response to VSV-M2 and ligands to RIG-I and MDA5

VSV-M2 is recognized by cytosolic RIG-I. Notably, 5'-triphosphate RNA molecules derived from either viral RNA or from the synthetically produced 3pRNA can also induce RIG-I activation. MDA5 stimulation is achieved using complexed poly(I:C), a synthetic analog of viral dsRNA. To test whether the RIG-I and MDA5 ligands 3pRNA and poly(I:C) can be used in their complexed structures to decipher RNA virus-induced sickness behavior in vivo, we first compared the tissue-specific signaling pathways after systemic challenge with VSV-M2 and the RIG-I and MDA5 ligands, respectively. A whole-genome expression analysis using splenic cells was carried out using an Affymetrix Mouse Gene 2.1 ST Array. Adult wt mice were injected with either VSV-M2, 3pRNA or complexed poly(I:C); 18h (VSV) or 24h later spleens were removed for RNA extraction and hybridization on Affymetrix arrays.

水泡性口炎病毒M2（VSV-M2）可被胞质视黄酸诱导基因蛋白I（RIG-I）识别。值得注意的是，无论是源自病毒RNA的5'-三磷酸RNA分子，还是人工合成的3pRNA，均可诱导RIG-I活化。黑色素瘤分化相关基因5（MDA5）的激活需通过复合形式的聚肌胞苷酸（poly(I:C)）实现——该物质是模拟病毒双链RNA的合成类似物。为验证RIG-I配体3pRNA与MDA5配体复合式poly(I:C)能否以其复合结构，用于解析体内RNA病毒诱导的疾病行为，我们首先分别对比了经全身性攻毒VSV-M2、RIG-I配体3pRNA与MDA5配体复合poly(I:C)后，组织特异性的信号通路变化。本研究采用Affymetrix小鼠基因2.1 ST阵列芯片，对脾脏细胞开展全基因组表达分析。将成年野生型（wt）小鼠分别注射VSV-M2、3pRNA或复合式poly(I:C)，分别于18小时（VSV-M2组）或24小时后摘取脾脏，用于RNA提取及Affymetrix芯片杂交。