Chlorella virus NY-2A encodes at least 12 DNA endonuclease/methyltransferase genes.
Chlorella virus NY-2A encodes at least 12 DNA endonuclease/methyltransferase genes.
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小球藻病毒 NY-2A 编码至少 12 个 DNA 核酸内切酶/甲基转移酶基因。
DOI：
10.1006/viro.1997.8936
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
VanEtten,JL
中科院分区：
文献类型：
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作者：
Zhang,Y;Nelson,M;Nietfeldt,J;Xia,Y;Burbank,D;Ropp,S;VanEtten,JL
380-kb的大肠杆菌病毒NY-2A基因组高度甲基化; 45%的胞嘧啶是5-甲基胞嘧啶（5 mC），37%的腺嘌呤是N6-甲基腺嘌呤（6 mA）。基于NY-2A DNA对80种甲基化敏感的DNA限制性内切酶的敏感性/抗性，预测该病毒编码至少10种DNA甲基转移酶：7种6 mA特异性甲基转移酶，M.CviQI（GTmAC）、M. CviQII（RmAR）、M.CviQIII（TCGmA）、M.CviQIV（GmATC）、M.CviQV（TGCmA）、M. CviQVI（GmANTC）和M.CviQVII（CmATG）;和3种5 mC特异性甲基转移酶，M.CviQVIII [RGmC（T/C/G）]、M.CviQIX（mCC）和M.CviQX（mCGR）。克隆了5个6 mA甲基转移酶基因，即M.CviQI、M. CviQIII、M.CviQV、M.CviQVI和M.CviQVII。此外，在NY-2A病毒感染的小球藻的无细胞提取物中检测到2种位点特异性内切酶活性，R.CviQI（G/TAC）和NY 2A-切口酶（R/AG）。因此，NY-2A基因组含有至少12个DNA甲基转移酶和核酸内切酶基因，它们总共构成病毒基因组的约3-4%。
The 380-kb chlorella virus NY-2A genome is highly methylated; 45% of the cytosines are 5-methylcytosine (5mC) and 37% of the adenines are N6-methyladenine (6mA). Based on the sensitivity/resistance of NY-2A DNA to 80 methylation-sensitive DNA restriction endonucleases, the virus is predicted to encode at least 10 DNA methyltransferases: 7 6mA-specific methyltransferases, M.CviQI (GTmAC), M.CvQII (RmAR), M.CviQIII (TCGmA), M.CviQIV (GmATC), M.CviQV (TGCmA), M.CviQVI (GmANTC), and M.CviQVII (CmATG); and 3 5mC-specific methyltransferases, M.CviQVIII [RGmC(T/C/G)], M.CviQIX (mCC), and M.CviQX (mCGR). Five of the 6mA methyltransferase genes,M.CviQI, M.CviQIII, M.CviQV, M.CviQVI,andM.CviQVII,were cloned and sequenced. In addition, 2 site-specific endonuclease activities, R.CviQI (G/TAC) and NY2A-nickase (R/AG), were detected in cell-free extracts from NY-2A virus-infected chlorella. Therefore, the NY-2A genome contains at least 12 DNA methyltransferase and endonuclease genes which, altogether, compose about 3–4% of the virus genome.