Evolutionary instability of the major histocompatibility complex class I loci in New World primates
Evolutionary instability of the major histocompatibility complex class I loci in New World primates
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DOI：
10.1073/pnas.94.26.14536
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发表时间：
1997-12-23
影响因子：
11.1
通讯作者：
Watkins, DI
中科院分区：
文献类型：
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作者：
Cadavid, LF;Shufflebotham, C;Watkins, DI
人类主要组织相容性复合体（MHC）HLA-A、-B、-E、-F和-G基因座的同源物存在于所有卡鼻动物（旧大陆灵长类、猿和人类）中，并且它们的一些等位基因谱系在几次物种形成事件中幸存下来。对来自新大陆灵长类动物7个不同属的26个MHC I类cDNA的分析表明，Callitrichinae（绢毛猴和绒猴）是MHC稳定性规则的例外。在灵长类动物MHC I类基因的基因树中，来自Callitrichinae的序列以属特异性方式聚集，而在新世界灵长类动物的其他属中，如Catarrhini，它们以跨属方式聚集。属特异性聚类的Callitrichinae的cDNA表明，有没有直系同源性的MHC I类基因座在本系统群的属。此外，与所有其他灵长类动物表现出的高变异性相比，Callitrichinae属的MHC I类基因表现出有限的变异性。因此，每个Callitrichinae属，表达自己的一套MHC I类基因，这表明一个异常高的周转率的位点发生在这个亚科。在Callitrichinae的MHC I类基因的有限的变异性可能是最近的起源，这些位点的结果。
Homologues of the human major histocompatibility complex (MHC) HLA-A, -B, -E, -F, and -G loci are present in all the Catarrhini (Old World primates, apes, and humans), and some of their allelic lineages have survived several speciation events. Analysis of 26 MHC class I cDNAs from seven different genera of New World primates revealed that the Callitrichinae (tamarins and marmosets) are an exception to these rules of MHC stability. In gene trees of primate MHC class I genes, sequences from the Callitrichinae cluster in a genus-specific fashion, whereas in the other genera of New World primates, as in the Catarrhini, they cluster in a transgeneric way. The genus-specific clustering of the Callitrichinae cDNAs indicates that there is no orthology between MHC class I loci in genera of this phyletic group. Additionally, the Callitrichinae genera exhibit limited variability of their MHC class I genes, in contrast to the high variability displayed by all other primates. Each Callitrichinae genus, therefore, expresses its own set of MHC class I genes, suggesting that an unusually high rate of turnover of loci occurs in this subfamily. The limited variability of MHC class I genes in the Callitrichinae is likely the result of the recent origin of these loci.