Diseases caused by animal virus infection seriously restricts the healthy development of animal husbandry.In-depth study of the molecular mechanism of viral replication and pathogenesis will provide theoretical basis for screening vaccine and drug targets.N6-methyladenosine(m6 A)modification occurs extensively in viral and host transcriptomes and affects viral replication and pathogenicity by regulating gene expression,which acts as a novel regulator of gene expression in addition to DNA and protein modifications.Insight into the regulatory molecular mechanism of m6 A modification in virus infection is the research hotspots and frontiers.In recent years,there are re-ports of alternation of the m6 A modification-associated epitranscriptomes and related function a-nalysis during virus infection.Here,we summarize the alternation of the epitranscriptomes induced by African swine fever virus(ASFV),porcine reproductive and respiratory syndrome virus(PRRSV),porcine epidemic diarrhoea virus(PEDV),cestode virus(CSFV),porcine pseudorabies virus(PRV),Marek's disease virus(MDV),Newcastle disease virus(NDV),avian leukaemia virus(ALV)and duck hepatitis A virus(DHAV)infection,and the subsequent effects on viral replica-tion and pathogenicity.We also discuss the potential role and molecular mechanism of m6 A modification in animal virus replication and pathogenesis,which will contributes to the prevention and control for animal disease.

Diseases caused by animal virus infection seriously restricts the healthy development of animal husbandry.In-depth study of the molecular mechanism of viral replication and pathogenesis will provide theoretical basis for screening vaccine and drug targets.N6-methyladenosine(m6 A)modification occurs extensively in viral and host transcriptomes and affects viral replication and pathogenicity by regulating gene expression,which acts as a novel regulator of gene expression in addition to DNA and protein modifications.Insight into the regulatory molecular mechanism of m6 A modification in virus infection is the research hotspots and frontiers.In recent years,there are re-ports of alternation of the m6 A modification-associated epitranscriptomes and related function a-nalysis during virus infection.Here,we summarize the alternation of the epitranscriptomes induced by African swine fever virus(ASFV),porcine reproductive and respiratory syndrome virus(PRRSV),porcine epidemic diarrhoea virus(PEDV),cestode virus(CSFV),porcine pseudorabies virus(PRV),Marek's disease virus(MDV),Newcastle disease virus(NDV),avian leukaemia virus(ALV)and duck hepatitis A virus(DHAV)infection,and the subsequent effects on viral replica-tion and pathogenicity.We also discuss the potential role and molecular mechanism of m6 A modification in animal virus replication and pathogenesis,which will contributes to the prevention and control for animal disease.

BACKGROUND: Tooth intrusion easily leads to root resorption. Previous studies regarding orthodontic treatment-caused tooth root resorption or retrospective clinical studies based on X-ray films have great errors in outcome evaluation because of intrusion force which cannot be precisely controlled. OBJECTIVE: This study established dog models of mini-implant anchorage for incisor intrusion to observe the histological changes of tooth root and periodontal tissue and to evaluate the feasibility and safety of mini-implant anchorage for incisor intrusion. METHODS: Nine dogs were assigned to one control group (n = 1) and four experimental groups per time to sacrifice (1, 2, 4 and 12 weeks; n = 2 dogs for each experimental group). No force was added to the control group. In the experimental groups, mini-implant as an anchorage was placed in the buccal alveoli between maxillary second and third incisors on each side. A traction force of 100 g was imposed to each side to intrude the maxillary first and second incisors on each side. At 1, 2, 3, and 4 weeks (traction force was imposed for 4 weeks and after withdrawal of extraction force, mini-implant was retained in place for 8 weeks), dogs were sacrificed. The first and second incisors together with gingival and alveolar bone were completely resected to prepare histological specimens. Following hematoxylin-eosin staining, histological changes of tooth root and periodontal tissue were observed. RESULTS AND CONCLUSION: Compared with the control group, in the 1-week group, histological changes were primarily at the root tip and alveolar ridge crest, alveolar bone and cementum were absorbed and peridental membrane presented glassy degeneration in local region; in the 2-week group, bone resorption degree and range were obviously enlarged, and bone resorption developed from root tip, root middle part to cervical part; in the 4-week group, bone resorption was still active and the glassy degeneration of peridental membrane disappeared; in the 12-week group, significant improvement in alveolar bone and cemental surface was observed, bone lacuna had deposition of newly formed bone, and peridental membrane was orderly arranged. These findings reveal that in the mini-implant anchorage for dog incisor intrusion, early histological changes primarily appear in the root tip and alveolar ridge crest, presenting as alveolar bone and cemental resorption and the glassy degeneration of the peridental membrane. Bone resorption extent and range expand with the persistence of traction force. After withdrawal of traction force, tooth root and periodontal tissue were gradually repaired