miRNA Regulatory Functions in Farm Animal Diseases, and Biomarker Potentials for Effective Therapies

Abstract

MicroRNAs (miRNAs) are small endogenous RNAs that regulate gene expression post-transcriptionally by targeting either the 3' untranslated or coding regions of genes. They have been reported to play key roles in a wide range of biological processes. The recent remarkable developments of transcriptomics technologies, especially next-generation sequencing technologies and advanced bioinformatics tools, allow more in-depth exploration of messenger RNAs (mRNAs) and non-coding RNAs (ncRNAs), including miRNAs. These technologies have offered great opportunities for a deeper exploration of miRNA involvement in farm animal diseases, as well as livestock productivity and welfare. In this review, we provide an overview of the current knowledge of miRNA roles in major farm animal diseases with a particular focus on diseases of economic importance. In addition, we discuss the steps and future perspectives of using miRNAs as biomarkers and molecular therapy for livestock disease management as well as the challenges and opportunities for understanding the regulatory mechanisms of miRNAs related to disease pathogenesis.

Keywords: Marek’s disease; PRRSV; RNAi therapy; biomarkers; foot-and-mouth disease; livestock diseases; mastitis; miRNAs; regulatory networks.

Figure 1

An overview of steps involved in the development of miRNA biomarkers for livestock disease management: (A) steps/stages to follow in miRNA biomarker development; (B) factors to consider in miRNA biomarker development; (C) potential application of miRNA biomarkers.

Figure 2

miRNAs in livestock diseases. Each V node represents an miRNA (blue V nodes (outer circle) represent miRNAs associated to one disease, and red V nodes (inner circle) present miRNAs associated to more than one disease) and each yellow hexagon node represents a livestock disease. FDM: foot and mouth disease; PRRS: porcine reproductive and respiratory syndrome; ASV: African swine fever virus; MD: Marek’s disease; BD: bursal disease; CD: chronic respiratory diseases; PPR: Peste des petits ruminants; CC: Cystic echinococcosis; EAC: enzootic nasal adenocarcinoma; BT: bluetongue; JD: Johne’s Disease.