CiAPEX2 and CiP0, candidates of AP endonucleases in Ciona intestinalis, have 3'-5' exonuclease activity and contribute to protection against oxidative stress.
CiAPEX2 and CiP0, candidates of AP endonucleases in Ciona intestinalis, have 3'-5' exonuclease activity and contribute to protection against oxidative stress.
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DOI：
10.1186/s41021-017-0087-7
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Zhang-Akiyama QM
中科院分区：
文献类型：
--
作者：
Funakoshi M;Nambara D;Hayashi Y;Zhang-Akiyama QM
脱嘌呤/脱嘧啶(AP)部位是最常见的DNA损伤之一。AP位点抑制转录和DNA复制，并诱导细胞死亡。AP内切酶是AP位点修复的关键酶。AP内切酶有几种类型，如AP内切酶2(APEX2)和核糖体蛋白P0(P0)。然而，目前尚不清楚不同的AP内切酶的功能和作用有何不同。为了阐明AP内切酶之间的作用差异，我们对黄瓜APEX2和P0同源物进行了生化分析。氨基酸序列分析表明，CiAPEX2和CiP0是AP内切酶同源物。虽然我们没有检测到AP内切酶和3‘-磷酸二酯酶活性，但这两个纯化的蛋白显示了3’-5‘外切酶活性。该酶的3‘-5’外切酶活性对乙二胺四乙酸(EDTA)敏感，底物DNA的3‘端影响该酶的活性。CiAPEX2和CiP0不仅能降解5‘端突出的DNA，还能降解AP核酸内切酶1(APEX1)产生的缺口DNA。这两个基因部分互补了过氧化氢处理的AP内切酶缺陷型大肠杆菌的生长速度。这些结果表明，3‘-5’核酸外切酶活性是APEX2和P0同系物的进化保守的酶活性，这种酶活性对AP内切酶可能是重要的。本文的在线版本(10.1186/s41021-0170087-7)包含补充材料，可供授权用户使用。
Apurinic/apyrimidinic (AP) sites are one of the most frequent DNA lesions. AP sites inhibit transcription and DNA replication, and induce cell death. AP endonucleases are key enzymes in AP site repair. Several types of AP endonucleases have been reported, such as AP endonuclease 2 (APEX2) and ribosomal protein P0 (P0). However, it is not known how the functions and roles differ among AP endonucleases. To clarify the difference of roles among AP endonucleases, we conducted biochemical analysis focused on APEX2 and P0 homologues in Ciona intestinalis. Amino acid sequence analysis suggested that CiAPEX2 and CiP0 are AP endonuclease homologues. Although we could not detect AP endonuclease or 3′-phosphodiesterase activity, these two purified proteins exhibited 3′-5′ exonuclease activity. This 3′-5′ exonuclease activity was sensitive to ethylenediaminetetraacetic acid (EDTA), and the efficiency of this activity was influenced by the 3′-terminus of substrate DNA. Both CiAPEX2 and CiP0 degraded not only a 5′-protruding DNA end, but also nicked DNA, which is generated through AP endonuclease 1 (APEX1) cleavage. These two genes partially complemented the growth rate of AP endonuclease-deficient Escherichia coli treated with hydrogen peroxide. These results indicate that 3′-5′ exonuclease activity is an evolutionarily conserved enzymatic activity of APEX2 and P0 homologues and this enzymatic activity may be important for AP endonucleases. The online version of this article (10.1186/s41021-017-0087-7) contains supplementary material, which is available to authorized users.
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影响因子：
2.6
作者：
Jin, G.;Zhang, Q. -M.;Yonei, S.
通讯作者：
Yonei, S.
DOI：
10.1073/pnas.88.24.11450
发表时间：
1991-12-01
影响因子：
11.1
作者：
DEMPLE, B;HERMAN, T;CHEN, DS
通讯作者：
CHEN, DS
影响因子：
14.9
作者：
CHEN, DS;HERMAN, T;DEMPLE, B
通讯作者：
DEMPLE, B
影响因子：
4.8
作者：
Kerins, SM;Collins, R;McCarthy, TV
通讯作者：
McCarthy, TV
影响因子：
5.6
作者：
Hadi, MZ;Ginalski, K;Wilson, DM
通讯作者：
Wilson, DM