A Hicks Julie, Yoo Dongwan, Liu Hsiao-Ching
Department of Animal Science, North Carolina State University, Raleigh, North Carolina, United States of America.
PLoS One. 2013 Dec 5;8(12):e82054. doi: 10.1371/journal.pone.0082054. eCollection 2013.
Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), a member of the arterivirus family, is the causative agent of Porcine Reproductive and Respiratory Syndrome (PRRS). PRRS is characterized by late term abortions and respiratory disease, particularly in young pigs. Small regulatory RNAs termed microRNA (miRNA) are associated with gene regulation at the post-transcriptional level. MiRNAs are known to play many diverse and complex roles in viral infections. To discover the impact of PRRSV infections on the cellular miRNAome, Illumina deep sequencing was used to construct small RNA expression profiles from in vitro cultured PRRSV-infected porcine alveolar macrophages (PAMs). A total of forty cellular miRNAs were significantly differentially expressed within the first 48 hours post infection (hpi). The expression of six miRNAs, miR-30a-3p, miR-132, miR-27b*, miR-29b, miR-146a and miR-9-2, were altered at more than one time point. Target gene identification suggests that these miRNAs are involved in regulating immune signaling pathways, cytokine, and transcription factor production. The most highly repressed miRNA at 24 hpi was miR-147. A miR-147 mimic was utilized to maintain miR-147 levels in PRRSV-infected PAMs. PRRSV replication was negatively impacted by high levels of miR-147. Whether down-regulation of miR-147 is directly induced by PRRSV or if it is part of the cellular response and PRRSV indirectly benefits remains to be determined. No evidence could be found of PRRSV-encoded miRNAs. Overall, the present study has revealed that a large and diverse group of miRNAs are expressed in swine alveolar macrophages and that the expression of a subset of these miRNAs is altered in PRRSV infected macrophages.
猪繁殖与呼吸综合征病毒（PRRSV）是动脉炎病毒科的成员，是猪繁殖与呼吸综合征（PRRS）的病原体。PRRS的特征是晚期流产和呼吸道疾病，尤其是在仔猪中。被称为微小RNA（miRNA）的小调节RNA与转录后水平的基因调控有关。已知miRNA在病毒感染中发挥许多不同且复杂的作用。为了发现PRRSV感染对细胞miRNA组的影响，使用Illumina深度测序从体外培养的PRRSV感染的猪肺泡巨噬细胞（PAM）构建小RNA表达谱。在感染后48小时内，共有40种细胞miRNA显著差异表达。六种miRNA，即miR-30a-3p、miR-132、miR-27b*、miR-29b、miR-146a和miR-9-2的表达在多个时间点发生了改变。靶基因鉴定表明这些miRNA参与调节免疫信号通路、细胞因子和转录因子的产生。在感染后24小时抑制程度最高的miRNA是miR-147。使用miR-147模拟物来维持PRRSV感染的PAM中miR-147的水平。高水平的miR-147对PRRSV复制产生负面影响。miR-147的下调是由PRRSV直接诱导的，还是它是细胞反应的一部分且PRRSV间接受益，仍有待确定。未发现PRRSV编码的miRNA的证据。总体而言，本研究表明在猪肺泡巨噬细胞中表达了大量且多样的miRNA，并且在PRRSV感染的巨噬细胞中这些miRNA的一个子集的表达发生了改变。
