Braithwaite Elena K, Prasad Rajendra, Shock David D, Hou Esther W, Beard William A, Wilson Samuel H
Laboratory of Structural Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
J Biol Chem. 2005 May 6;280(18):18469-75. doi: 10.1074/jbc.M411864200. Epub 2005 Mar 3.
Mammalian DNA polymerase (pol) lambda is a member of the X-family of DNA polymerases and has striking enzymatic and structural similarities to mammalian DNA pol beta. Because pol beta provides two important enzymatic activities for base excision repair (BER), we examined whether pol lambda might also contribute to BER. We used extracts from mouse embryonic fibroblasts representing wild-type and null genotypes for pol beta and pol lambda. In combination with neutralizing antibodies against pol beta and pol lambda, our results show a BER deficiency in the pol lambda -/- cell extract compared with extract from isogenic wild-type cells. In addition, the pol lambda antibody strongly reduced in vitro BER in the pol beta -/- cell extract. These data indicate that pol lambda is able to contribute to BER in mouse fibroblast cell extract.
哺乳动物DNA聚合酶（pol）λ是DNA聚合酶X家族的成员，与哺乳动物DNA polβ具有显著的酶学和结构相似性。由于polβ为碱基切除修复（BER）提供两种重要的酶活性，我们研究了polλ是否也对BER有贡献。我们使用了来自代表polβ和polλ野生型和缺失基因型的小鼠胚胎成纤维细胞的提取物。结合针对polβ和polλ的中和抗体，我们的结果显示，与同基因野生型细胞的提取物相比，polλ-/-细胞提取物中存在BER缺陷。此外，polλ抗体在很大程度上降低了polβ-/-细胞提取物中的体外BER。这些数据表明，polλ能够在小鼠成纤维细胞提取物中对BER发挥作用。
