{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T16:37:22Z","timestamp":1753893442820,"version":"3.41.2"},"reference-count":56,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,3,31]],"date-time":"2025-03-31T00:00:00Z","timestamp":1743379200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>Toxocariasis, caused by the dog roundworm <jats:italic>Toxocara canis,<\/jats:italic> is a globally distributed zoonotic parasitic disease that poses a significant threat to veterinary and public health. The ubiquitin plus an L40 ribosomal protein (UBQ-2) in parasites plays a crucial role in protein degradation and meiotic divisions, thereby affecting parasite development, survival, and parasite\u2013host interactions. In this study, we identified for the first time a full-length cDNA encoding the UBQ-2 protein from the <jats:italic>T. canis<\/jats:italic>-omic dataset, called Tcubq-2. After cloning and sequencing, we conducted sequence analysis and structural modeling of TcUBQ-2 using online bioinformatics tools. The recombinant TcUBQ-2 protein (rTcUBQ-2) was prokaryotically expressed and subjected to Western blot analysis to assess its antigenicity and immunoreactivity. Additionally, we performed immunolocalization of the endogenous protein in adult <jats:italic>T. canis<\/jats:italic> and evaluated its serodiagnostic potential using sera from na\u00efve and infected mice and dogs. Our results showed that the complete cDNA sequence of Tcubq-2 was 387\u202fbp in length and encoded a polypeptide of 128 amino acids, lacking both an N-terminal signal sequence and a transmembrane domain. Sequence and phylogenetic analyses showed that TcUBQ-2 shared the closest genetic distance with its homologs in <jats:italic>Parascaris univalens<\/jats:italic> and <jats:italic>Ascaris suum<\/jats:italic>. Real-time quantitative PCR and Western blotting revealed an expression peak of TcUBQ-2 in the intestine-hatched second-stage (L3) larvae compared to other developmental stages of <jats:italic>T. canis<\/jats:italic>. Tissue localization of endogenous TcUBQ-2 revealed its broad distributions in the body wall, muscle, gut epithelium, and microvilli of adult <jats:italic>T. canis,<\/jats:italic> with gender-specific expression in the uterus, ovary, and non-embryonated eggs of females. Based on its strong immunogenic properties, a recombinant TcUBQ-2 (rTcUBQ-2)-based ELISA was established and exhibited a sensitivity of 100% and a specificity of 95.8% to detect anti-<jats:italic>T. canis<\/jats:italic> mouse sera and a sensitivity of 79.2% and a specificity of 83.3% to detect anti-<jats:italic>T. canis<\/jats:italic> dog sera, respectively. This study presents a comprehensive bioinformatics analysis of the dog roundworm TcUBQ-2, and its strong serodiagnostic performance suggests that rTcUBQ-2 has the potential to be developed into an ELISA-based serological test for detecting toxocariasis in dogs and other accidental hosts, including humans.<\/jats:p>","DOI":"10.3389\/fvets.2025.1550489","type":"journal-article","created":{"date-parts":[[2025,3,31]],"date-time":"2025-03-31T13:59:14Z","timestamp":1743429554000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Cloning, bioinformatics analysis, and expression of the ubiquitin 2 (ubq-2) gene from the dog roundworm Toxocara canis"],"prefix":"10.3389","volume":"12","author":[{"given":"Pengchen","family":"Zhu","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xin","family":"Hu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiali","family":"Huang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lidan","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhao","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruixi","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinyi","family":"Fan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guoshan","family":"Wei","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qin","family":"He","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhaoruiyi","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuan","family":"Zhou","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hui","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yue","family":"Xie","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2025,3,31]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"3369","DOI":"10.1007\/s00436-020-06769-2","article-title":"Efficacy 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