Appearance and disappearance of Syk family protein-tyrosine kinase genes during metazoan evolution.
Appearance and disappearance of Syk family protein-tyrosine kinase genes during metazoan evolution.
复制标题
Syk家族蛋白酪氨酸激酶基因在后生动物进化过程中的出现和消失。
DOI：
10.1016/s0378-1119(99)00373-x
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发表时间：
1999
期刊：
影响因子：
3.5
通讯作者：
Sakaguchi,M
中科院分区：
文献类型：
--
作者：
Steele,RE;Stover,NA;Sakaguchi,M
Syk家族蛋白酪氨酸激酶是哺乳动物淋巴细胞中免疫受体信号传导的重要组成部分。秀丽隐杆线虫基因组中不存在Syk基因表明该激酶家族是最近进化起源的。令人惊讶的是，我们已经发现，水螅，早期分歧的动物刺胞门的成员，包含一个基因编码的Syk激酶。系统发育分析表明，一个单一的Syk家族基因存在于动物之前的基因复制，产生Syk和ZAP-70，两个哺乳动物Syk家族基因。C.秀丽线虫也缺乏鲨鱼蛋白酪氨酸激酶基因，我们发现它是Syk家族姐妹群的成员。我们的结论是Syk和Shark基因都从C.优雅的。这种天然基因敲除结果表明，无论是Syk还是Shark激酶都不是线虫和其他后生动物之间共同拥有的过程所必需的。Hydra Syk基因在上皮细胞中表达，该位点与Hydra Syk识别外来细胞的作用一致。
Syk family protein-tyrosine kinases are essential components of immunoreceptor signaling in mammalian lymphocytes. The absence of Syk genes from the Caenorhabiditis elegans genome suggests that this kinase family is of recent evolutionary origin. Surprisingly, we have found that Hydra vulgaris, a member of the early diverging animal phylum Cnidaria, contains a gene encoding a Syk kinase. Phylogenetic analysis indicates that a single Syk family gene was present in animals prior to the gene duplication that gave rise to Syk and ZAP-70, the two mammalian Syk family genes. C. elegans also lacks a Shark protein-tyrosine kinase gene, which we show is a member of a sister group to the Syk family. We conclude that both Syk and Shark genes were lost from the genome of an ancestor of C. elegans. This natural gene knockout result indicates that neither Syk nor Shark kinases are essential for processes held in common between the nematode and other metazoans. The Hydra Syk gene is expressed in epithelial cells, a site consistent with a role for Hydra Syk in recognition of foreign cells.