Molecular Characterization and Expression Analysis of miR-29a in Porcine Cells and Porcine Reproductive and Respiratory Syndrome Virus Infected Peripheral Blood Mononuclear Cells

Abstract

MicroRNAs are a group of small non-coding RNA that are involved in posttranscriptional regulation through target mRNA degradation or inhibition of protein synthesis. The objective of this present study was to characterize and determine expression level of porcine miR-29a in various tissues. Our results indicated that porcine miR-29a shared high conserved sequence with miR-29a from other organisms. Furthermore, in silico analysis suggested that the seed region of porcine miR-29a partially matched IFN-γ mRNA. RT-PCR analysis indicated that miR-29a expressed in various tissues including lymph node, spleen, peripheral blood mononuclear cells (PBMCs) and PK-15 cells. Expression profiling of miR-29a in PRRSV-infected PBMCs in vitro revealed an upregulation at 24 and 48 h. Moreover, expression analysis of miR-29a showed higher transcripts in both low pathogenic and highly pathogenic-PRRSV infected pigs. Together, all of these results revealed that porcine miR-29a was highly conserved with miR-29a from other organisms and miR-29a transcripts increased in PRRSV-infected PBMCs both in vitro and in vivo. Additional studies of the role of miR-29a will provide valuable information on virus: host interaction and could be applied for PRRS control in the future.