The gamma-globin genes and their flanking sequences in primates: findings with nucleotide sequences of capuchin monkey and tarsier.
The gamma-globin genes and their flanking sequences in primates: findings with nucleotide sequences of capuchin monkey and tarsier.
复制标题
灵长类动物的伽马珠蛋白基因及其侧翼序列：卷尾猴和眼镜猴的核苷酸序列的发现。
DOI：
10.1006/geno.1993.1422
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发表时间：
1993
期刊：
影响因子：
4.4
通讯作者：
Slightom,JL
中科院分区：
文献类型：
--
作者：
Hayasaka,K;Skinner,CG;Goodman,M;Slightom,JL
通过对卷尾猴（新世界猴）和眼镜猴（原猴）β-珠蛋白基因簇的广泛区域进行测序，我们证实卷尾猴和眼镜猴分别有两个和一个γ-珠蛋白基因。这些发现表明，祖先的类人猿γ-珠蛋白基因在类人猿从眼镜猴分化出来之后复制，但在它们分化成阔鼻猴（新世界猴）和卡他鼻猴（旧世界猴，猿和人类）之前。卷尾猴γ1-珠蛋白基因启动子区积累了许多核苷酸替换，包括近端CCAAT元件中的T到C替换。这种反向突变，沿着先前发现的蜘蛛猴γ 1位点是假基因，提示阔鼻类γ2珠蛋白基因可能是原始胎儿β样珠蛋白基因。比对的γ基因序列在5′侧翼区含有多个6 bp或更长的保守序列元件（系统发育足迹），而在3′侧翼区没有。基因转换主要发生在重复基因的5′侧翼和转录区，而很少发生在3′侧翼序列。然而，在卷尾猴和蜘蛛猴启动子区域内没有转换，这表明在阔鼻猴中选择对转换起作用，因为它们可以降低（或抑制）γ 2表达。
By sequencing extensive regions of the β-globin gene cluster from capuchin monkey (New World monkey) and tarsier (prosimian) we confirmed that capuchin monkey and tarsier have two and one γ-globin gene(s), respectively. These findings indicate that the ancestral anthropoid γ-globin gene duplicated after anthropoids diverged from tarsier, but before they diverged into platyrrhines (New World monkeys) and catarrhines (Old World monkeys, apes, and human). The capuchin monkey γ1-globin gene promoter region accumulated many nucleotide substitutions, including a T to C substitution in the proximal CCAAT element. This adverse mutation, along with the previous finding that the γ1locus in spider monkey is a pseudogene, suggests that in platyrrhines the γ2-globin gene may be the primary fetal β-like globin gene. The aligned γ gene sequences contain several conserved sequence elements (phylogenetic footprint) of 6 bp or longer in the 5′ flanking region, but none in the 3′ flanking region. Gene conversions frequently occurred in the 5′ flanking and transcribed regions of the duplicated genes of anthropoids but rarely in the 3′ flanking sequences. However, an absence of conversions within the capuchin and spider monkeys promoter regions suggests that in platyrrhines selection acted against conversions as they could decrease (or inactivate) γ2expression.