澳大利亚莫纳什大学Jérôme Le Nours等研究人员合作揭示有袋动物γμ T细胞受体的分子组装模式。相关论文发表在2021年3月26日出版的《科学》杂志上。

研究人员报道了仅在非真兽类哺乳动物中发现的γμ T细胞受体（TCR）群体，其由两个结构域（Vγ-Cμ）的γ链和三个结构域（Vμ-Vμj-Cμ）的μ链组成。γμ TCR的特征在于Vγ和Vμj域中的多样性受限，以及一个高度不同的Vμ域。

两个不同的γμ TCR的晶体结构揭示了γμ TCR异二聚体结合的结构基础。Vμ结构域具有单结构域抗体的特征，其中高度可变的CDR3μ环提示了主要的抗原识别决定簇。因此，研究人员定义了第三种TCR谱系γμ TCR组装的分子基础。

据悉，αβ和γδ TCR是高度多样化的抗原受体，它们定义了两种进化保守的T细胞谱系。 

附：英文原文

Title: The molecular assembly of the marsupial γμ T cell receptor defines a third T cell lineage

Author: Kimberly A. Morrissey, Marcin Wegrecki, T. Praveena, Victoria L. Hansen, Lijing Bu, Komagal Kannan Sivaraman, Samuel Darko, Daniel C. Douek, Jamie Rossjohn, Robert D. Miller, Jérme Le Nours

Issue&Volume: 2021/03/26

Abstract: αβ and γδ T cell receptors (TCRs) are highly diverse antigen receptors that define two evolutionarily conserved T cell lineages. We describe a population of γμTCRs found exclusively in non-eutherian mammals that consist of a two-domain (Vγ-Cγ) γ-chain paired to a three-domain (Vμ-Vμj-Cμ) μ-chain. γμTCRs were characterized by restricted diversity in the Vγ and Vμj domains and a highly diverse unpaired Vμ domain. Crystal structures of two distinct γμTCRs revealed the structural basis of the association of the γμTCR heterodimer. The Vμ domain shared the characteristics of a single-domain antibody within which the hypervariable CDR3μ loop suggests a major antigen recognition determinant. We define here the molecular basis underpinning the assembly of a third TCR lineage, the γμTCR.

DOI: 10.1126/science.abe7070

Source: https://science.sciencemag.org/content/371/6536/1383