{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T09:30:07Z","timestamp":1781170207235,"version":"3.54.1"},"reference-count":41,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,21]],"date-time":"2023-04-21T00:00:00Z","timestamp":1682035200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key R&amp;D Program of China","award":["2022YFD2400405"],"award-info":[{"award-number":["2022YFD2400405"]}]},{"name":"National Key R&amp;D Program of China","award":["32072295"],"award-info":[{"award-number":["32072295"]}]},{"name":"National Key R&amp;D Program of China","award":["2023ZLYS02"],"award-info":[{"award-number":["2023ZLYS02"]}]},{"name":"National Natural Science Foundation","award":["2022YFD2400405"],"award-info":[{"award-number":["2022YFD2400405"]}]},{"name":"National Natural Science Foundation","award":["32072295"],"award-info":[{"award-number":["32072295"]}]},{"name":"National Natural Science Foundation","award":["2023ZLYS02"],"award-info":[{"award-number":["2023ZLYS02"]}]},{"name":"Shandong Key R&amp;D Program","award":["2022YFD2400405"],"award-info":[{"award-number":["2022YFD2400405"]}]},{"name":"Shandong Key R&amp;D Program","award":["32072295"],"award-info":[{"award-number":["32072295"]}]},{"name":"Shandong Key R&amp;D Program","award":["2023ZLYS02"],"award-info":[{"award-number":["2023ZLYS02"]}]},{"name":"Taishan Scholar Climbing Project Fund of Shandong, China","award":["2022YFD2400405"],"award-info":[{"award-number":["2022YFD2400405"]}]},{"name":"Taishan Scholar Climbing Project Fund of Shandong, China","award":["32072295"],"award-info":[{"award-number":["32072295"]}]},{"name":"Taishan Scholar Climbing Project Fund of Shandong, China","award":["2023ZLYS02"],"award-info":[{"award-number":["2023ZLYS02"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The Chinese tongue sole (Cynoglossus semilaevis) is a traditional, precious fish in China. Due to the large growth difference between males and females, the investigation of their sex determination and differentiation mechanisms receives a great deal of attention. Forkhead Box O (FoxO) plays versatile roles in the regulation of sex differentiation and reproduction. Our recent transcriptomic analysis has shown that foxo genes may participate in the male differentiation and spermatogenesis of Chinese tongue sole. In this study, six Csfoxo members (Csfoxo1a, Csfoxo3a, Csfoxo3b, Csfoxo4, Csfoxo6-like, and Csfoxo1a-like) were identified. Phylogenetic analysis indicated that these six members were clustered into four groups corresponding to their denomination. The expression patterns of the gonads at different developmental stages were further analyzed. All members showed high levels of expression in the early stages (before 6 months post-hatching), and this expression was male-biased. In addition, promoter analysis found that the addition of C\/EBP\u03b1 and c-Jun transcription factors enhanced the transcriptional activities of Csfoxo1a, Csfoxo3a, Csfoxo3b, and Csfoxo4. The siRNA-mediated knockdown of the Csfoxo1a, Csfoxo3a, and Csfoxo3b genes in the testicular cell line of Chinese tongue sole affected the expression of genes related to sex differentiation and spermatogenesis. These results have broadened the understanding of foxo\u2019s function and provide valuable data for studying the male differentiation of tongue sole.<\/jats:p>","DOI":"10.3390\/ijms24087625","type":"journal-article","created":{"date-parts":[[2023,4,21]],"date-time":"2023-04-21T03:01:48Z","timestamp":1682046108000},"page":"7625","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Identification and Functional Analysis of foxo Genes in Chinese Tongue Sole (Cynoglossus semilaevis)"],"prefix":"10.3390","volume":"24","author":[{"given":"Tingting","family":"Zhang","sequence":"first","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"},{"name":"School of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengqian","family":"Zhang","sequence":"additional","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuxuan","family":"Sun","sequence":"additional","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lu","family":"Li","sequence":"additional","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peng","family":"Cheng","sequence":"additional","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xihong","family":"Li","sequence":"additional","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2135-090X","authenticated-orcid":false,"given":"Na","family":"Wang","sequence":"additional","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Songlin","family":"Chen","sequence":"additional","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3887-9973","authenticated-orcid":false,"given":"Wenteng","family":"Xu","sequence":"additional","affiliation":[{"name":"Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences (CAFS), Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1038\/nrg2523","article-title":"The evolution of Fox genes and their role in development and disease","volume":"10","author":"Hannenhalli","year":"2009","journal-title":"Nat. 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