{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,25]],"date-time":"2026-02-25T06:19:55Z","timestamp":1772000395496,"version":"3.50.1"},"reference-count":54,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T00:00:00Z","timestamp":1771372800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the NSFC-Yunnan Joint Fund","award":["U2202201"],"award-info":[{"award-number":["U2202201"]}]},{"name":"the Research Fund of Shanxi Province for Introduced High-level Leading Talents","award":["RFSXIHLT202101"],"award-info":[{"award-number":["RFSXIHLT202101"]}]},{"name":"the Special Research Fund of Shanxi Agricultural University for High-level Talents","award":["2021XG001"],"award-info":[{"award-number":["2021XG001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The highly efficient endodyogeny of tachyzoites is a key process driving acute infection by Toxoplasma gondii. The centrocone is a specialized and critical structure for parasite cell division, but the regulatory mechanisms of centrocone proteins in T. gondii remain poorly understood. In this study, we characterized the centrocone protein SMC_N1, which exhibited periodic expression in tachyzoites, peaking during the synthesis phase. Conditional depletion of SMC_N1 was achieved in the type I RH strain and type II cyst-forming PRU strain using the mAID system combined with CRISPR-Cas9. Depletion of SMC_N1 disrupted IMC assembly, endodyogeny and nuclear division, as well as the stable inheritance of the apicoplast and centrosome, resulting in severe defects in intracellular replication and impaired tachyzoite growth. Collectively, these results indicate that SMC_N1 regulates cell division by coordinating organelle inheritance and cytoskeletal dynamics, ensuring proper replication of T. gondii tachyzoites and provide insights into mechanisms controlling parasite proliferation.<\/jats:p>","DOI":"10.3390\/ani16040653","type":"journal-article","created":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T15:28:18Z","timestamp":1771428498000},"page":"653","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Centrocone Protein SMC_N1 Is Important for the Proliferation of Toxoplasma gondii Tachyzoites"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-6567-2202","authenticated-orcid":false,"given":"Chuan","family":"Li","sequence":"first","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jin","family":"Gao","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3724-0776","authenticated-orcid":false,"given":"Xiao-Jing","family":"Wu","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4512-4632","authenticated-orcid":false,"given":"Shi-Chen","family":"Xie","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hai-Sheng","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2530-4628","authenticated-orcid":false,"given":"Xing-Quan","family":"Zhu","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/j.ijpara.2020.11.001","article-title":"Control of human toxoplasmosis","volume":"51","author":"Smith","year":"2021","journal-title":"Int. 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