biostudies-literatureUnknown14Xie TNational Natural Science Foundation of ChinaAgriculture Research System of ChinaAutophagy plays an important role in host antiviral defense. The avian leukosis virus subgroup J (ALV-J) has been shown to inhibit autophagy while promoting viral replication. The underlying autophagic mechanisms, however, are unknown. Cholesterol 25-hydroxylase (CH25H) is a conserved interferon-stimulated gene, which converts cholesterol to a soluble antiviral factor, 25-hydroxycholesterol (25HC). In this study, we further investigated the autophagic mechanism of CH25H resistance to ALV-J in chicken embryonic fibroblast cell lines (DF1). Our results found that overexpression of <i>CH25H</i> and treatment with 25HC promoted the autophagic markers microtubule-associated protein 1 light chain 3 II (LC3II) and autophagy-related gene 5(ATG5), while decreased autophagy substrate p62/SQSTM1 (p62Frontiers in immunology1093289https://www.ebi.ac.uk/biostudies/studies/S-EPMC9975585biostudies-literatureChicken CH25H inhibits ALV-J replication by promoting cellular autophagy.PMC9975585Xie TLi XFeng MShi MZhang XMo GfalseChicken CH25H inhibits ALV-J replication by promoting cellular autophagy.Autophagy plays an important role in host antiviral defense. The avian leukosis virus subgroup J (ALV-J) has been shown to inhibit autophagy while promoting viral replication. The underlying autophagic mechanisms, however, are unknown. Cholesterol 25-hydroxylase (CH25H) is a conserved interferon-stimulated gene, which converts cholesterol to a soluble antiviral factor, 25-hydroxycholesterol (25HC). In this study, we further investigated the autophagic mechanism of CH25H resistance to ALV-J in chicken embryonic fibroblast cell lines (DF1). Our results found that overexpression of <i>CH25H</i> and treatment with 25HC promoted the autophagic markers microtubule-associated protein 1 light chain 3 II (LC3II) and autophagy-related gene 5(ATG5), while decreased autophagy substrate p62/SQSTM1 (p622023-01-01T00:00:00Z20232025-04-19T22:26:38.958Z2025-02-19T02:21:22.104ZS-EPMC99755853687512210.3389/fimmu.2023.1093289