Lerner A, Diener A C, Reinherz E L, Clayton L K
Laboratory of Immunobiology, Harvard Medical School, Boston, MA.
Eur J Immunol. 1992 Aug;22(8):2135-40. doi: 10.1002/eji.1830220826.
We have cloned and sequenced human genomic DNA homologous to exons 9 and 10 of the CD3 zeta/eta/theta locus. Although there are open reading frames within the human sequences corresponding to the translated portions of murine exons 9 and 10, we find no evidence of conservation of the encoded polypeptide product. Furthermore, using oligonucleotides derived from these homologous sequences, we are unable to detect human CD3 eta- or CD3 theta-like transcripts by polymerase chain reaction amplification of reverse-transcribed RNA from a variety of human lymphoid tissues. Despite the absence of evidence for conservation of human CD3 eta and CD3 theta, there is a surprising degree of similarity between human and murine nucleotide sequences, not only for exons 9 and 10 (78% and 70%, respectively), but also for the 9/10 intron (71%). A possible mechanism for this conservation is discussed.
我们已经克隆并测序了与CD3 ζ/η/θ基因座外显子9和10同源的人类基因组DNA。尽管人类序列中存在与小鼠外显子9和10的翻译部分相对应的开放阅读框，但我们没有发现编码的多肽产物保守性的证据。此外，使用从这些同源序列衍生的寡核苷酸，我们无法通过聚合酶链反应扩增来自各种人类淋巴组织的逆转录RNA来检测人类CD3 η或CD3 θ样转录本。尽管缺乏人类CD3 η和CD3 θ保守性的证据，但人类和小鼠核苷酸序列之间存在惊人程度的相似性，不仅外显子9和10（分别为78%和70%），而且9/10内含子（71%）也是如此。本文讨论了这种保守性的一种可能机制。
