{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T16:31:24Z","timestamp":1762360284911,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T00:00:00Z","timestamp":1762300800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Innovation Program of the Chinese Academy of Agricultural Sciences","award":["CAAS-CSLPDCP-202402"],"award-info":[{"award-number":["CAAS-CSLPDCP-202402"]}]},{"DOI":"10.13039\/100007219","name":"Shanghai Municipal Natural Science Foundation","doi-asserted-by":"publisher","award":["2023-02-08-00-12-F04617"],"award-info":[{"award-number":["2023-02-08-00-12-F04617"]}],"id":[{"id":"10.13039\/100007219","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Duck enteritis virus (DEV), an epornitic pathogen, causes substantial economic losses in the commercial duck industry and poses persistent risks to wild and migratory waterfowl populations. However, due to the large genomic capacity of the DEV, the understanding of the virulence-associated genes of DEV is still limited. In previous studies, we developed an attenuated strain E74 by serial passage of a virulent strain E1 on primary chicken embryo fibroblasts (CEFs). The bird experiment showed that the mortality rate of E1 on ducks reached 100%, and high-titered viruses were detected in all tested tissue samples. In contrast, the E74 virus has lost its pathogenicity in ducks and can only be detected at a relatively low viral load in the spleen. Furthermore, the E74 stimulated a significant increase in antibodies in the ducks at 7 days post-inoculation. To further investigate the molecular basis of the attenuation of DEV in ducks, the complete genomes of E74 and E1 were sequenced and analyzed. Compared with E1, E74 had a 5152 bp deletion in the UL region, which resulted in the lack of the hypothetical protein, LORF5, UL55 and LORF4 genes. To test the influence of the deletion on the viral pathogenicity, a rescued virus rE1-\u03945152 with the 5152 bp deletion in the UL region was generated on the E1 backbone. Animal experiments showed that the lethality of rE1-\u03945152 in ducks had disappeared. Those findings suggest that the hypothetical protein, LORF5, UL55, and LORF4 genes of DEV are associated with virus virulence, and the flexibility of this region provided excellent insertion sites for exogenous genes when DEV is used as a recombinant vaccine vector.<\/jats:p>","DOI":"10.3390\/microorganisms13112537","type":"journal-article","created":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T16:09:47Z","timestamp":1762358987000},"page":"2537","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Pathogenicity Evaluation and Virulence Gene Identification of an Attenuated Duck Enteritis Virus"],"prefix":"10.3390","volume":"13","author":[{"given":"Xiaona","family":"Shi","sequence":"first","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haibin","family":"Zhuang","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dun","family":"Shuo","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-9265-060X","authenticated-orcid":false,"given":"Luzhao","family":"Li","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shenghui","family":"Pan","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zihua","family":"Wu","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mei","family":"Tang","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenxia","family":"Yang","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9516-2130","authenticated-orcid":false,"given":"Qinfang","family":"Liu","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chunxiu","family":"Yuan","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8039-4668","authenticated-orcid":false,"given":"Dawei","family":"Yan","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xue","family":"Pan","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bangfeng","family":"Xu","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhifei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-9037-5328","authenticated-orcid":false,"given":"Minghao","family":"Yan","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiaoyang","family":"Teng","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zejun","family":"Li","sequence":"additional","affiliation":[{"name":"Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kong, J., Feng, K., Zhao, Q., Chen, Y., Wang, J., Chen, S., Shao, G., Liao, L., Li, Y., and Xie, Z. (2022). Pathogenicity and transmissibility studies on live attenuated duck enteritis virus vaccine in non-target species. Front. Microbiol., 13.","DOI":"10.3389\/fmicb.2022.979368"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1080\/01652176.2017.1298885","article-title":"Duck virus enteritis (duck plague)\u2014A comprehensive update","volume":"37","author":"Dhama","year":"2017","journal-title":"Vet. Q."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1111\/tbed.13002","article-title":"Molecular and pathological characterization of duck enteritis virus in Egypt","volume":"66","author":"Hamed","year":"2019","journal-title":"Transbound. Emerg. Dis."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1016\/j.antiviral.2012.12.015","article-title":"Recombinant duck enteritis virus works as a single-dose vaccine in broilers providing rapid protection against H5N1 influenza infection","volume":"97","author":"Liu","year":"2013","journal-title":"Antiviral Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1016\/j.virol.2009.06.018","article-title":"Molecular characterization of the genome of duck enteritis virus","volume":"391","author":"Li","year":"2009","journal-title":"Virology"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Liu, R., Gao, L., Yang, F., Li, X., Liu, C., Qi, X., Cui, H., Zhang, Y., Wang, S., and Wang, X. (2022). Duck Enteritis Virus Protein Kinase US3 Inhibits DNA Sensing Signaling by Phosphorylating Interferon Regulatory Factor 7. Microbiol. Spectr., 10.","DOI":"10.1128\/spectrum.02299-22"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Gao, L., Liu, R., Yang, F., Li, X., Liu, C., Qi, X., Cui, H., Zhang, Y., Wang, S., and Wang, X. (2022). Duck Enteritis Virus Inhibits the cGAS-STINGDNA-Sensing Pathway To Evade the Innate Immune Response. J. Virol., 96.","DOI":"10.1128\/jvi.01578-22"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"104281","DOI":"10.1016\/j.jprot.2021.104281","article-title":"Proteomic analysis of host cellular proteins co-immunoprecipitated with duck enteritis virus, gC","volume":"245","author":"Chen","year":"2021","journal-title":"J. Proteom."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1016\/j.virusres.2011.07.004","article-title":"Complete genome sequence of virulent duck enteritis virus (DEV) strain 2085 and comparison with genome sequences of virulent and attenuated DEV strains","volume":"160","author":"Wang","year":"2011","journal-title":"Virus Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"5965","DOI":"10.1128\/JVI.00529-12","article-title":"Complete genomic sequence of Chinese virulent duck enteritis virus","volume":"86","author":"Wu","year":"2012","journal-title":"J. Virol."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Yang, F., Liu, P., Li, X., Liu, R., Gao, L., Cui, H., Zhang, Y., Liu, C., Qi, X., and Pan, Q. (2021). Recombinant Duck Enteritis Virus-Vectored Bivalent Vaccine Effectively Protects Against Duck Hepatitis A Virus Infection in Ducks. Front. Microbiol., 12.","DOI":"10.3389\/fmicb.2021.813010"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1016\/j.vetmic.2019.04.022","article-title":"Recombinant duck enteritis viruses expressing the Newcastle disease virus (NDV) F gene protects chickens from lethal NDV challenge","volume":"232","author":"Ding","year":"2019","journal-title":"Vet. Microbiol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"13841","DOI":"10.1128\/JVI.01517-12","article-title":"Comparative genomic analysis of duck enteritis virus strains","volume":"86","author":"Wu","year":"2012","journal-title":"J. Virol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/j.antiviral.2016.03.003","article-title":"Recombinant duck enteritis viruses expressing major structural proteins of the infectious bronchitis virus provide protection against infectious bronchitis in chickens","volume":"130","author":"Li","year":"2016","journal-title":"Antivir. Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2284301","DOI":"10.1080\/22221751.2023.2284301","article-title":"Recombinant duck enteritis virus bearing the hemagglutinin genes of H5 and H7 influenza viruses is an ideal multivalent live vaccine in ducks","volume":"13","author":"Zhao","year":"2024","journal-title":"Emerg. Microbes Infect."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"200","DOI":"10.1186\/1743-422X-8-200","article-title":"Different linkages in the long short regions of the genomes of duck enteritis virus Clone-03 VAC strains","volume":"8","author":"Liu","year":"2011","journal-title":"Virol. J."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1186\/s13567-020-00859-w","article-title":"Duck enteritis virus pUL47, as a late structural protein localized in the nucleus, mainly depends on residues 40 to 50 and 768 to 777 and inhibits IFN-\u03b2 signalling by interacting with STAT1","volume":"51","author":"He","year":"2020","journal-title":"Vet. Res."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1915","DOI":"10.3382\/ps.2010-00848","article-title":"Development and application of an indirect immunohistochemical method for the detection of duck plague virus vaccine antigens in paraffin sections and localization in the vaccinated duckling tissues","volume":"89","author":"Shen","year":"2010","journal-title":"Poult. Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1016\/j.vetmic.2016.03.001","article-title":"Attenuated Salmonella Typhimurium delivery of a novel DNA vaccine induces immune responses and provides protection against duck enteritis virus","volume":"186","author":"Liu","year":"2016","journal-title":"Vet. Microbiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1186\/s13567-015-0174-3","article-title":"Efficient strategy for constructing duck enteritis virus-based live attenuated vaccine against homologous and heterologous H5N1 avian influenza virus and duck enteritis virus infection","volume":"46","author":"Zou","year":"2015","journal-title":"Vet. Res."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Zou, Z., Ma, J., Huang, K., Chen, H., Liu, Z., and Jin, M. (2016). Live Attenuated Vaccine Based on Duck Enteritis Virus against Duck Hepatitis A Virus Types 1 and 3. Front. Microbiol., 7.","DOI":"10.3389\/fmicb.2016.01613"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1186\/s12985-023-02053-8","article-title":"Pathogenicity immunogenicity of gI\/gE\/TK-gene-deleted Felid herpesvirus 1 variants in cats","volume":"20","author":"Tang","year":"2023","journal-title":"Virol. J."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"8943","DOI":"10.1016\/j.vaccine.2011.09.050","article-title":"Attenuation of bovine herpesvirus type 1 by deletion of its glycoprotein G and tk genes and protection against virulent viral challenge","volume":"29","author":"Zhang","year":"2011","journal-title":"Vaccine"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Ruan, P., Feng, X., Cheng, A., Wang, M., Zhang, W., Wu, Y., Yang, Q., Tian, B., Ou, X., and Sun, D. (2022). Evaluation of safety and immunogenicity of duck-plague virus gC\/gE double gene deletion. Front. Immunol., 13.","DOI":"10.3389\/fimmu.2022.963009"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Koyanagi, N., Takeshima, K., Shio, S., Maruzuru, Y., Kato, A., and Kawaguchi, Y. (2025). Identification of viral activators of the HSV-2 UL13 protein kinase. J. Virol., 99.","DOI":"10.1128\/jvi.01165-25"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Shen, B., Li, Y., Cheng, A., Wang, M., Wu, Y., Yang, Q., Jia, R., Tian, B., Ou, X., and Mao, S. (2021). The LORF5 Gene Is Non-essential for Replication but Important for Duck Plague Virus Cell-to-Cell Spread Efficiently in Host Cells. Front. Microbiol., 12.","DOI":"10.3389\/fmicb.2021.744408"}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/13\/11\/2537\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T16:27:14Z","timestamp":1762360034000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/13\/11\/2537"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,5]]},"references-count":26,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2025,11]]}},"alternative-id":["microorganisms13112537"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms13112537","relation":{},"ISSN":["2076-2607"],"issn-type":[{"value":"2076-2607","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,5]]}}}