APOBEC-2, a cardiac- and skeletal muscle-specific member of the cytidine deaminase supergene family
APOBEC-2, a cardiac- and skeletal muscle-specific member of the cytidine deaminase supergene family
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DOI：
10.1006/bbrc.1999.0925
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发表时间：
1999-07-05
影响因子：
3.1
通讯作者：
Chan, L
中科院分区：
文献类型：
--
作者：
Liao, W;Hong, SH;Chan, L
apobec1介导载脂蛋白（apo） B mRNA的编辑，是胞苷脱氨酶超基因家族中C（胞苷）- > U（尿苷）编辑酶亚家族中唯一已知的成员。在这里，我们报道了该亚家族的另一个成员apobec2的克隆。人类和小鼠的apobec2均含有224个氨基酸残基，其基因定位于人类6号染色体（6p21）和小鼠17号染色体的共链区。系统发育分析表明，apobec2与apobec1在进化上存在亲缘关系，替代率分析表明，apobec2是一个比apobec1保守得多的基因。apobec2 mRNA和蛋白仅在心脏和骨骼肌中表达，apobec2不显示可检测的apoB mRNA编辑活性。与胞苷脱氨酶超家族的其他编辑酶一样，apobec2具有低但确定的内在胞苷脱氨酶活性。apobec2的鉴定表明，apobec1不是C- b> U编辑酶亚家族的唯一成员，与A（腺苷）- >I（肌苷）编辑酶亚家族一样，该亚家族必须包含至少两种甚至更多不同的脱氨酶。这表明影响apoB mRNA和其他rna的C- >U编辑不是由单一酶介导的孤立事件，而是涉及多个相关蛋白，这些蛋白是从与内控酶胞苷脱氨酶密切相关的原始基因进化而来的。(C) 1999学术出版社。
APOBEC-1, which mediates the editing of apolipoprotein (apo) B mRNA, is the only known member of the C (cytidine)--> U (uridine) editing enzyme subfamily of the cytidine deaminase supergene family. Here we report the cloning of APOBEC-2, another member of the subfamily. Human and mouse APOBEC-2 both contain 224 amino acid residues, and their genes are mapped to syntenic regions of human chromosome 6 (6p21) and mouse chromosome 17. By phylogenetic analysis, APOBEC-2 is shown to be evolutionarily related to APOBEC-1, and analysis of substitution rates indicates that APOBEC-2 is a much better conserved gene than APOBEC-1. APOBEC-2 mRNA and protein are expressed exclusively in heart and skeletal muscle, APOBEC-2 does not display detectable apoB mRNA editing activity. Like other editing enzymes of the cytidine deaminase superfamily, APOBEC-2 has low, but definite, intrinsic cytidine deaminase activity. The identification of APOBEC-2: indicates that APOBEC-1 is not the only member of the C-->U editing enzyme subfamily, which, Like the A (adenosine)-->I (inosine) subfamily of editing enzymes, must encompass at least two and possibly more different deaminase enzymes. It suggests that the C-->U editing affecting apoB mRNA and other RNAs is not an isolated event mediated by a single enzyme but involves multiple related proteins that have evolved from a primordial gene closely related to the housekeeping enzyme cytidine deaminase. (C) 1999 Academic Press.