De novo DNA synthesis by human DNA polymerase λ, DNA polymerase μ and terminal deoxyribonucleotidyl transferase
De novo DNA synthesis by human DNA polymerase λ, DNA polymerase μ and terminal deoxyribonucleotidyl transferase
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DOI：
10.1016/j.jmb.2004.03.056
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发表时间：
2004-05-28
影响因子：
5.6
通讯作者：
Hübscher, U
中科院分区：
文献类型：
--
作者：
Ramadan, K;Shevelev, IV;Hübscher, U
DNA 聚合酶 (pols) 催化 DNA 的合成。该反应需要引物模板 DNA，以便从引物的 3'OH 末端沿着模板生长。另一方面，末端脱氧核糖核苷酸转移酶 (TdT) 催化在 DNA 链 3'OH 末端添加核苷酸，无需模板。 pol lambda 和 pol mu 是普遍存在的酶，具有 DNA 聚合酶和末端脱氧核糖核苷酸转移酶活性，与 pol beta 和 TdT 一起属于 pol X 家族。在这里，我们证明了 pol lambda、pol mu 和 TdT 都具有在反应中没有引物模板或什至没有引物或模板的情况下体外合成 DNA 短片段的能力。 pol lambda、pol mu 和 TdT 从头合成的 DNA 似乎具有不寻常的结构。此外，我们发现pol lambda的氨基酸Phe506对于从头合成是必需的。这种新颖的催化活性可能与这三个 pol X 家族成员在 DNA 修复和 DNA 重组中的拟议功能有关。 (C) 2004 Elsevier Ltd. 保留所有权利。
DNA polymerases (pols) catalyse the synthesis of DNA. This reaction requires a primer-template DNA in order to grow from the 3'OH end of the primer along the template. On the other hand terminal deoxyribonucleotidyl transferase (TdT) catalyses the addition of nucleotides at the 3'OH end of a DNA strand, without the need of a template. Pol lambda and pol mu are ubiquitous enzymes, possess both DNA polymerase and terminal deoxyribonucleotidyl transferase activities and belong to pol X family, together with pol beta and TdT. Here we show that pol lambda, pol mu and TdT, all possess the ability to synthesise in vitro short fragments of DNA in the absence of a primer-template or even a primer or a template in the reaction. The DNA synthesised de novo by pol lambda, pol mu and TdT appears to have an unusual structure. Furthermore we found that the amino acid Phe506 of pol lambda is essential for the de novo synthesis. This novel catalytic activity might be related to the proposed functions of these three pol X family members in DNA repair and DNA recombination. (C) 2004 Elsevier Ltd. All rights reserved.