Uchiyama Yukinobu, Takeuchi Ryo, Kodera Hirofumi, Sakaguchi Kengo
Department of Applied Biological Science, Tokyo University of Science, Noda, Chiba, Japan.
Biochimie. 2009 Feb;91(2):165-70. doi: 10.1016/j.biochi.2008.07.005. Epub 2008 Jul 26.
Four types of DNA polymerase (Pol beta, Pol lambda, Pol mu and TdT) have been identified in eukaryotes as members of the polymerase X-family. Only vertebrates have all four types of enzyme. Plants and fungi have one or two X-family polymerases, while protostomes, such as fruit flies and nematodes, do not appear to have any. It is possible that the well-known metabolic pathways in which these enzymes are involved are restricted to the vertebrate world. The distribution of the DNA polymerases involved in DNA repair across the various biological kingdoms differs from that of the DNA polymerases involved in chromosomal DNA replication. In this review, we focus on the interesting pattern of distribution of the X-family enzymes across biological kingdoms and speculate on their roles.
在真核生物中已鉴定出四种DNA聚合酶（Polβ、Polλ、Polμ和TdT）作为聚合酶X家族的成员。只有脊椎动物拥有所有四种类型的酶。植物和真菌有一两种X家族聚合酶，而诸如果蝇和线虫等原口动物似乎没有任何X家族聚合酶。有可能这些酶所参与的著名代谢途径仅限于脊椎动物界。参与DNA修复的DNA聚合酶在各个生物界中的分布与参与染色体DNA复制的DNA聚合酶的分布不同。在本综述中，我们重点关注X家族酶在生物界中的有趣分布模式，并推测它们的作用。
