POSSIBLE ROLES OF BETA-ELIMINATION AND DELTA-ELIMINATION REACTIONS IN THE REPAIR OF DNA CONTAINING AP (APURINIC APYRIMIDINIC) SITES IN MAMMALIAN-CELLS
POSSIBLE ROLES OF BETA-ELIMINATION AND DELTA-ELIMINATION REACTIONS IN THE REPAIR OF DNA CONTAINING AP (APURINIC APYRIMIDINIC) SITES IN MAMMALIAN-CELLS
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DOI：
10.1042/bj2530553
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发表时间：
1988-07-15
影响因子：
4.1
通讯作者：
VERLY, WG
中科院分区：
文献类型：
--
作者：
BAILLY, V;VERLY, WG
组蛋白和多胺通过诱导。β来破坏DNA中磷酸二酯键3‘’到AP（无尿嘧啶/无嘧啶）位点。-消除反应，然后是-消除反应。这些度量。-和- -消除反应可能对染色质DNA中AP位点的修复有两种重要作用。在一种途径中，当磷酸二酯与AP位点的5‘’键被AP内切酶水解后，5‘’末端无碱基的5‘’磷酸糖通过β -消除被释放。由3' -OH和5' -磷酸端限制的单核苷酸间隙然后由DNA聚合酶-. β关闭。和DNA连接酶。我们已经在体外证明了这种修复是可能的。在另一种途径中，β - 3‘’进入AP位点。-先消去。我们已经证明，这样产生的3‘’端无碱基糖不能被染色质AP内切酶从大鼠肝脏释放。但它可以通过- δ消除释放，留下一个由3 " -磷酸和5 " -磷酸限制的间隙。在染色质3”-磷酸酶将3”-磷酸转化为3”-OH基团后，与AP内切酶和- β连续作用形成的核苷酸缺口一样，会有一个由3”-OH和5”-磷酸限制的单核苷酸缺口。-消除催化剂在第一个途径。
Histones and polyamines nick the phosphodiester bond 3'' to AP (apurinic/apyrimidinic) sites in DNA by inducing a .beta.-elimination reaction, which can be followed by .delta.-elimination. These .beta.- and .delta.-elimination reactions might be important for the repair of AP sites in chromatin DNA in either of two ways. In one pathway, after the phosphodiester bond 5'' to the AP site has been hydrolyzed with an AP endonuclease, the 5''-terminal base-free sugar 5''-phosphate is released by .beta.-elimination. The one-nucleotide gap limited by 3''-OH and 5''-phosphate ends is then closed by DNA polymerase-.beta. and DNA ligase. We have shown in vitro that such a repair is possible. In the other pathway, the nicking 3'' to the AP site by .beta.-elimination occurs first. We have shown that the 3''-terminal base-free sugar so produced cannot be released by the chromatin AP endonuclease from rat liver. But it can be released by .delta.-elimination, leaving a gap limited by 3''-phosphate and 5''-phosphate. After conversion of the 3''-phosphate into a 3''-OH group by the chromatin 3''-phosphatase, there will be the same one-nucleotide gap, limited by 3''-OH and 5''-phosphate, as that formed by the successive actions of the AP endonuclease and the .beta.-elimination catalyst in the first pathway.