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Updated: May 22, 2026
09:05
MicroRNA-based Regulation of Picornavirus Tropism
Published on: February 6, 2017
Natural polymorphisms in the bovine leukemia virus microRNA cluster modulate miRNA expression and host regulatory
Aneta Pluta1,2, Kerstin Skovgaard3, Konrad Józef Dębski4
1Department of Virology and Viral Animal Diseases, National Veterinary Research Institute, 24-100, Puławy, Poland. aneta.pluta@piwet.pulawy.pl.
Veterinary Research
|May 21, 2026
Summary
Natural genetic variations in bovine leukemia virus (BLV) microRNAs (miRNAs) affect their expression and alter host gene regulation. These BLV miRNA polymorphisms influence immune responses and viral persistence.
Area of Science:
- Virology
- Genetics
- Immunology
Background:
- Bovine leukemia virus (BLV) expresses microRNAs (miRNAs) during latency.
- Naturally occurring single-nucleotide polymorphisms (SNPs) in the BLV miRNA locus are common but functionally uncharacterized.
- Understanding these variations is crucial for comprehending host-virus interactions and viral persistence.
Purpose of the Study:
- To investigate the functional consequences of naturally occurring SNPs within the BLV miRNA locus.
- To determine how these polymorphisms affect miRNA output and host gene regulation.
- To explore the role of BLV miRNA variation in host-virus dynamics.
Main Methods:
- Sequencing of the BLV miRNA locus from naturally infected cattle.
- Functional evaluation of field-derived variants in HEK293T cells.
- Quantification of mature miRNA levels using stem-loop RT-qPCR.
- Assessment of host transcriptional responses via oligonucleotide microarrays.
- Bioinformatic identification of predicted miRNA targets.
Main Results:
- Identified 84 polymorphic sites within the BLV miRNA locus, many affecting regulatory elements and seed regions.
- Variant loci showed altered mature miRNA accumulation and shifts in predicted target repertoires.
- BLV miRNA polymorphisms modulated host gene expression, impacting innate immunity, interferon responses, antigen presentation, and tumor suppression.
- Significant overlap found between predicted miRNA targets and downregulated host transcripts.
Conclusions:
- Natural polymorphisms within the BLV miRNA cluster modulate miRNA expression and host regulatory pathways.
- Sequence variation in the viral miRNA locus contributes to differential host-virus interactions.
- BLV miRNA polymorphisms may influence mechanisms supporting viral persistence.
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