Characterizing Host microRNA: Virus Interactions of Orthoavulavirus javaense

Area of Science:

• Virology
• Molecular Biology
• Genomics

Background:

• MicroRNAs (miRNAs) regulate gene expression through sequence complementarity with target transcripts.
• Viruses may exploit host miRNA machinery to modulate host gene expression during infection.
• Orthoavulavirus javaense (OAVJ) causes Newcastle disease, impacting poultry economically.

Purpose of the Study:

• To investigate if OAVJ genomes contain sequences that mimic or complement host miRNA seed sites.
• To determine if viral seed mimics (vSMs) or viral seed sponges (vSSs) influence host gene regulation during OAVJ infection.
• To compare vSM and vSS content between low-virulence (lentogenic) and virulent (velogenic) OAVJ strains.

Main Methods:

• Computational analysis of OAVJ genomes from lentogenic and velogenic strains.
• Identification and characterization of viral seed mimics (vSMs) and viral seed sponges (vSSs).
• Analysis of secondary RNA structures flanking vSMs and vSSs.
• Experimental validation of miRNA-host gene interactions.

Main Results:

• OAVJ genomes harbor vSMs and vSSs capable of interacting with host miRNAs.
• Velogenic OAVJ strains possess a significantly higher number of vSMs and fewer vSSs compared to lentogenic strains.
• Viral transcripts exhibit structural features similar to miRNA precursors.
• Modulation of vSS-miR-27b-5p affected P gene expression in a sequence-dependent manner.

Conclusions:

• Viral transcripts can interfere with host miRNA-mediated gene regulation.
• Differences in vSM and vSS content may correlate with OAVJ virulence.
• OAVJ utilizes host miRNA pathways to alter cellular processes and infection outcomes.