Comparative screening identifies gga-miR-204 as a nutrient-responsive miRNA that targets MAP1LC3B and promotes infectious bursal disease virus replication in HD11 cells

Infectious bursal disease virus (IBDV) is a highly contagious immunosuppressive pathogen that causes substantial economic losses to the poultry industry. Although metabolic pathways and key metabolic genes involved in viral replication have been extensively studied, systematic approaches for identifying nutrient-responsive microRNAs (miRNAs) that functionally regulate IBDV replication remain limited. In this study, amino acid- and glucose-starvation models were established in chicken HD11 macrophages and integrated with IBDV infection-associated miRNA profiling to comparatively screen for nutrient-responsive miRNAs potentially involved in viral replication. Short-term nutrient deprivation altered LC3-associated molecular phenotypes and reduced IBDV VP2 protein expression. Small RNA sequencing revealed that nutrient starvation and IBDV infection induced distinct but partially overlapping miRNA expression profiles, with predicted target genes enriched mainly in metabolic and stress-response pathways. gga-miR-204 was upregulated under amino acid and glucose starvation but downregulated following IBDV infection. Functional assays showed that gga-miR-204 overexpression increased viral RNA levels, VP2 protein expression, and infectious virus production, whereas inhibition of endogenous gga-miR-204 suppressed IBDV replication. Reporter assays supported targeting of the chicken MAP1LC3B 3' untranslated region by gga-miR-204, and mimic treatment reduced LC3-II abundance in HD11 cells. MAP1LC3B silencing increased VP2 abundance, whereas MAP1LC3B overexpression decreased it. These findings identify gga-miR-204 as a nutrient-responsive miRNA that promotes IBDV replication in HD11 cells and support MAP1LC3B as a candidate target with functional effects on VP2 abundance. Whether MAP1LC3B mediates the proviral effect of gga-miR-204 remains to be established. This comparative screening approach provides a starting point for identifying nutrient-responsive miRNAs and investigating their potential roles in linking cellular metabolic state to IBDV replication.