{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T10:57:25Z","timestamp":1769857045596,"version":"3.49.0"},"reference-count":58,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2022,7,7]],"date-time":"2022-07-07T00:00:00Z","timestamp":1657152000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Central Public-interest Scientific Institution Basal Research Fund, CAFS","award":["2020XT08"],"award-info":[{"award-number":["2020XT08"]}]},{"name":"Central Public-interest Scientific Institution Basal Research Fund, CAFS","award":["2020TD44"],"award-info":[{"award-number":["2020TD44"]}]},{"name":"Central Public-interest Scientific Institution Basal Research Fund, CAFS","award":["2020TD33"],"award-info":[{"award-number":["2020TD33"]}]},{"name":"Central Public-interest Scientific Institution Basal Research Fund, CAFS","award":["YFI202207"],"award-info":[{"award-number":["YFI202207"]}]},{"name":"Central Public-interest Scientific Institution Basal Research Fund, CAFS","award":["32060824"],"award-info":[{"award-number":["32060824"]}]},{"name":"Central Public-interest Scientific Institution Basal Research Fund, CAFS","award":["31360634"],"award-info":[{"award-number":["31360634"]}]},{"name":"National Natural Science Foundation of China","award":["2020XT08"],"award-info":[{"award-number":["2020XT08"]}]},{"name":"National Natural Science Foundation of China","award":["2020TD44"],"award-info":[{"award-number":["2020TD44"]}]},{"name":"National Natural Science Foundation of China","award":["2020TD33"],"award-info":[{"award-number":["2020TD33"]}]},{"name":"National Natural Science Foundation of China","award":["YFI202207"],"award-info":[{"award-number":["YFI202207"]}]},{"name":"National Natural Science Foundation of China","award":["32060824"],"award-info":[{"award-number":["32060824"]}]},{"name":"National Natural Science Foundation of China","award":["31360634"],"award-info":[{"award-number":["31360634"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>In immature lymphocytes, recombination activating genes 1 and 2 are necessary for antigen receptor V (D) J recombination, representing immature lymphocyte biomarkers. Herein, we cloned and sequenced rice-field eel rag1 and rag2 genes. Their expressions in the thymus, liver, and kidney were significant from 0 days post hatching (dph) to 45 dph, peaking at 45 dph in these three tissues. In situ hybridization detected high rag1 and rag2 expressions in the liver, kidney, and thymus of rice-field eel from 2 to 45 dph, suggesting that multiple tissues of rice-field eel contain lymphocyte lineage cells and undergo lymphopoiesis. Tissue morphology was used to observe lymphopoiesis development in these three tissues. The thymus primordium began to develop at 2 dph, while the kidney and liver have generated. Our findings verified that the thymus is the primary lymphopoietic tissue and suggested that, in rice-field eel, lymphocyte differentiation also occurs in the liver and kidney.<\/jats:p>","DOI":"10.3390\/ijms23147546","type":"journal-article","created":{"date-parts":[[2022,7,7]],"date-time":"2022-07-07T22:11:47Z","timestamp":1657231907000},"page":"7546","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Rag1 and Rag2 Gene Expressions Identify Lymphopoietic Tissues in Larvae of Rice-Field Eel (Monopterus albus)"],"prefix":"10.3390","volume":"23","author":[{"given":"Yuchen","family":"Liu","sequence":"first","affiliation":[{"name":"Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China"},{"name":"National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nan","family":"Jiang","sequence":"additional","affiliation":[{"name":"Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenzhi","family":"Liu","sequence":"additional","affiliation":[{"name":"Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0373-5734","authenticated-orcid":false,"given":"Yong","family":"Zhou","sequence":"additional","affiliation":[{"name":"Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3370-5712","authenticated-orcid":false,"given":"Mingyang","family":"Xue","sequence":"additional","affiliation":[{"name":"Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiwang","family":"Zhong","sequence":"additional","affiliation":[{"name":"College of Biological Science and Engineering, Jiangxi Agricultural University, Nanchang 330045, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhong","family":"Li","sequence":"additional","affiliation":[{"name":"Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7291-2493","authenticated-orcid":false,"given":"Yuding","family":"Fan","sequence":"additional","affiliation":[{"name":"Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China"},{"name":"National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China"},{"name":"College of Biological Science and Engineering, Jiangxi Agricultural University, Nanchang 330045, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,7]]},"reference":[{"key":"ref_1","first-page":"505","article-title":"The embryonic and postembryonic development of Monopterus albus","volume":"27","author":"Zhou","year":"2003","journal-title":"J. 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