Núñez-Hernández Fernando, Vera Gonzalo, Sánchez Armand, Rodríguez Fernando, Núñez José I
Institut de Recerca i Tecnologia Agroalimentàries (IRTA)-Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
Centre de Recerca en Agrigenòmica (CRAG), Consorci CSIC-IRTA-UAB-UB, Bellaterra, Barcelona, Spain.
BMC Vet Res. 2018 Sep 3;14(1):268. doi: 10.1186/s12917-018-1601-2.
African swine fever virus (ASFV) is the etiological agent of African swine fever (ASF), a re-expanding devastating and highly lethal hemorrhagic viral disease. microRNAs (miRNAs) are a new class of small non-coding RNAs that regulate gene expression post-transcriptionally. The discovery of virus specific miRNAs has increased both in number and importance in the past few years. We have recently described the differential expression of several porcine miRNAs during in vivo infection with attenuated and virulent ASFV strains. Here, we have extended these studies trying to identify the presence of viral miRNAs encoded by ASFV in an in vivo infection in pigs.
Sixteen small RNA libraries were analyzed from spleen and submandibular lymph nodes obtained from eight pigs, seven infected with either the virulent E75 ASFV strain or its attenuated counterpart E75CV1, or from pigs surviving E75CV1-infection and challenged with BA71 (heterologous challenge) and one non infected as negative control. Samples were recovered at different times post-infection. Libraries were analyzed by next-generation sequencing. Some viral miRNA candidates were initially identified, which did not correspond to porcine miRNAs. Further structural analyses were carried out in order to confirm if they met the conformational requirements to be considered a viral miRNA.
The analysis of sixteen small RNA libraries prepared from two different tissues obtained from pigs experimentally infected with E75, E75CV1 or with E75CV1 plus BA71, revealed the presence of six potential miRNA sequences but none of them met the requirements to be considered as viral miRNAs. Thus, we can conclude that ASFV does not express miRNAs in vivo, at least under the experimental conditions described here.
非洲猪瘟病毒（ASFV）是非洲猪瘟（ASF）的病原体，这是一种再度肆虐且极具致死性的出血性病毒性疾病。微小RNA（miRNA）是一类新型的小非编码RNA，可在转录后调节基因表达。在过去几年中，病毒特异性miRNA的发现数量和重要性都有所增加。我们最近描述了在体内感染减毒和强毒ASFV毒株期间几种猪miRNA的差异表达。在此，我们扩展了这些研究，试图在猪的体内感染中鉴定由ASFV编码的病毒miRNA的存在。
分析了从八头猪的脾脏和下颌下淋巴结获得的16个小RNA文库，其中七头猪感染了强毒E75 ASFV毒株或其减毒株E75CV1，或者是在感染E75CV1后存活并接受BA71（异源攻击）攻击的猪，还有一头未感染的猪作为阴性对照。在感染后的不同时间采集样本。通过下一代测序分析文库。最初鉴定出了一些病毒miRNA候选物，它们与猪miRNA不对应。进一步进行了结构分析，以确认它们是否符合被视为病毒miRNA的构象要求。
对从实验感染E75、E75CV1或E75CV1加BA71的猪的两种不同组织制备的16个小RNA文库的分析显示，存在六个潜在的miRNA序列，但它们均不符合被视为病毒miRNA的要求。因此，我们可以得出结论，至少在此处描述的实验条件下，ASFV在体内不表达miRNA。
