Ultraviolet damage endonuclease (Uve1p): A structure and strand-specific DNA endonuclease
Ultraviolet damage endonuclease (Uve1p): A structure and strand-specific DNA endonuclease
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DOI：
10.1021/bi000189r
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发表时间：
2000-05-16
期刊：
影响因子：
2.9
通讯作者：
Doetsch, PW
中科院分区：
文献类型：
--
作者：
Kaur, B;Doetsch, PW
粟酒裂殖酵母紫外线损伤核酸内切酶（UVDE或Uve1p）在紫外线诱导的DNA损伤的替代切除修复途径中执行初始步骤。这种DNA修复途径最初被认为是紫外线损伤的特异性。然而，Uve1p的广泛底物特异性表明这种酶具有更普遍的作用。Uve1p识别UV诱导的双嘧啶光加合物和其他非UV诱导的DNA加合物。生化和遗传分析也表明，Uve1p可能参与协调体内错配修复。这项研究表明，Uve1p识别和切割具有小的未配对环的异源双链DNA，但不识别长度为6至8个核苷酸的环。此外，该酶不会识别具有回文插入的DNA，这些插入可能形成碱基配对的发夹结构。Uve1p的切割效率取决于与DNA末端错配的距离，这表明3'末端可能有助于Uve1p的链识别信号。这些生化活动的背景下，Uve1p在DNA修复中的作用进行了讨论。
Schizosaccharomyces pombe ultraviolet damage endonuclease (UVDE or Uve1p) performs the initial step in an alternative excision repair pathway for UV-induced DNA damage. This DNA repair pathway was originally thought to be specific for UV damage. However, the broad substrate specificity of Uve1p suggests a more general role for this enzyme. Uve1p recognizes UV-induced bipyrimidine photoadducts and other non-UV-induced DNA adducts. Biochemical and genetic analysis also suggests that Uve1p may be involved in orchestrating mismatch repair in vivo. This study demonstrates that Uve1p recognizes and cleaves heteroduplex DNA with small unpaired loops but does not recognize loops six to eight nucleotides in length. In addition, the enzyme does not recognize DNA with palindromic insertions that could form base-paired hairpin structures. The cleavage efficiency of Uve1p depends on the distance of a mismatch from the DNA terminus, suggesting that the 3' terminus may contribute to the strand discrimination signal for Uve1p. These biochemical activities are discussed in the context of the role of Uve1p in DNA repair.