{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T15:31:01Z","timestamp":1776353461691,"version":"3.51.2"},"reference-count":42,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2020,8,1]],"date-time":"2020-08-01T00:00:00Z","timestamp":1596240000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2020,8,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>Atypical TCR\u03b4 found in sharks, amphibians, birds, and monotremes and TCR\u03bc found in monotremes and marsupials are TCR chains that use Ig or BCR-like variable domains (VH\u03b4\/V\u03bc) rather than conventional TCR V domains. These unconventional TCR are consistent with a scenario in which TCR and BCR, although having diverged from each other more than 400 million years ago, continue to exchange variable gene segments in generating diversity for Ag recognition. However, the process underlying this exchange and leading to the evolution of these atypical TCR receptor genes remains elusive. In this study, we identified two TCR\u03b1\/\u03b4 gene loci in the Chinese alligator (Alligator sinensis). In total, there were 144 V, 154 J\u03b1, nine J\u03b4, eight D\u03b4, two C\u03b1, and five C\u03b4 gene segments in the TCR\u03b1\/\u03b4 loci of the Chinese alligator, representing the most complicated TCR\u03b1\/\u03b4 gene system in both genomic structure and gene content in any tetrapod examined so far. A pool of 32 VH\u03b4 genes divided into 18 subfamilies was found to be scattered over the two loci. Phylogenetic analyses revealed that these VH\u03b4 genes could be related to bird VH\u03b4 genes, VH\u03b4\/V\u03bc genes in platypus or opossum, or alligator VH genes. Based on these findings, a model explaining the evolutionary pattern of atypical TCR\u03b4\/TCR\u03bc genes in tetrapods is proposed. This study sheds new light on the evolution of TCR and BCR genes, two of the most essential components of adaptive immunity.<\/jats:p>","DOI":"10.4049\/jimmunol.2000257","type":"journal-article","created":{"date-parts":[[2020,6,26]],"date-time":"2020-06-26T23:04:53Z","timestamp":1593212693000},"page":"637-647","source":"Crossref","is-referenced-by-count":12,"title":["Analysis of the Chinese Alligator TCR\u03b1\/\u03b4 Loci Reveals the Evolutionary Pattern of Atypical TCR\u03b4\/TCR\u03bc in Tetrapods"],"prefix":"10.1093","volume":"205","author":[{"given":"Xifeng","family":"Wang","sequence":"first","affiliation":[{"name":"Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Plant Protection, China Agricultural University , Beijing 100193 ,","place":["People\u2019s Republic of China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jinwei","family":"Huang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of 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