Watkins D I, Chen Z W, Hughes A L, Evans M G, Tedder T F, Letvin N L
Harvard Medical School, New England Regional Primate Research Center, Southborough, Massachusetts 01772.
Nature. 1990 Jul 5;346(6279):60-3. doi: 10.1038/346060a0.
The products of the classical human major histocompatibility complex (MHC) class I genes (HLA-A, -B, -C) are highly polymorphic molecules that bind peptides and present them to T lymphocytes. The non-polymorphic, non-classical MHC class I gene products (HLA-E, -F, -G) are not restricting elements for the majority of T lymphocytes. The evolutionary relationship of the non-classical and classical MHC class I genes is unclear. Here we present the cloning and sequencing of the MHC class I genes of a New World primate, the cotton-top tamarin (Saguinus oedipus). The expressed MHC class I genes of this species are more closely related to the human non-classical HLA-G gene than they are to genes of the human classical HLA-A, -B, and -C loci. These observations imply that classical and non-classical genes do not necessarily constitute mutually exclusive groups over evolutionary time.
经典人类主要组织相容性复合体（MHC）I类基因（HLA - A、- B、- C）的产物是高度多态性的分子，它们结合肽段并将其呈递给T淋巴细胞。非多态性的非经典MHC I类基因产物（HLA - E、- F、- G）对大多数T淋巴细胞而言并非限制元件。非经典和经典MHC I类基因的进化关系尚不清楚。在此，我们展示了一种新世界灵长类动物——棉顶狨（Saguinus oedipus）的MHC I类基因的克隆与测序。该物种表达的MHC I类基因与人类非经典HLA - G基因的关系，比与人类经典HLA - A、- B和 - C基因座的基因关系更为密切。这些观察结果表明，在进化过程中，经典基因和非经典基因不一定构成相互排斥的群体。
