School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
Bioorg Med Chem. 2018 Aug 7;26(14):4168-4178. doi: 10.1016/j.bmc.2018.07.006. Epub 2018 Jul 5.
Bleomycin (BLM) is a cancer chemotherapeutic agent that cleaves cellular DNA at specific sequences. Using next-generation Illumina sequencing, the genome-wide sequence specificity of DNA cleavage by two BLM analogues, 6'-deoxy-BLM Z and zorbamycin (ZBM), was determined in human HeLa cells and compared with BLM. Over 200 million double-strand breaks were examined for each sample, and the 50,000 highest intensity cleavage sites were analysed. It was found that the DNA sequence specificity of the BLM analogues in human cells was different to BLM, especially at the cleavage site (position "0") and the "+1" position. In human cells, the 6'-deoxy-BLM Z had a preference for 5'-GTGYMC (where * is the cleavage site, Y is C or T, M is A or C); it was 5'-GTGYMCA for ZBM; and 5'-GTGTAC for BLM. With cellular DNA, the highest ranked tetranucleotides were 5'-TGCC and 5'-TGTA for 6'-deoxy-BLM Z; 5'-TGCC, 5'-TGTA and 5'-TGCA for ZBM; and 5'-TGTA for BLM. In purified human genomic DNA, the DNA sequence preference was 5'-TGTA for 6'-deoxy-BLM, 5'-RTGYAYR (where R is G or A) for ZBM, and 5'-TGTA for BLM. Thus, the sequence specificity of the BLM analogue, 6'-deoxy-BLM Z, was similar to BLM in purified human DNA, while ZBM was different.
博来霉素（BLM）是一种癌症化疗药物，可在特定序列处切割细胞 DNA。使用新一代 Illumina 测序技术，在人宫颈癌细胞（HeLa 细胞）中测定了两种 BLM 类似物 6'-脱氧 BLM Z 和佐比霉素（ZBM）对基因组范围的 DNA 切割的序列特异性，并与 BLM 进行了比较。每个样品检查了超过 2 亿个双链断裂，分析了 50000 个强度最高的切割位点。结果发现，BLM 类似物在人细胞中的 DNA 序列特异性与 BLM 不同，特别是在切割位点（位置“0”）和“+1”位置。在人细胞中，6'-脱氧 BLM Z 优先与 5'-GTGYMC（其中是切割位点，Y 是 C 或 T，M 是 A 或 C）结合；对于 ZBM 是 5'-GTGYMCA；对于 BLM 是 5'-GTGTAC。与细胞 DNA 结合时，排名最高的四核苷酸是 6'-脱氧 BLM Z 的 5'-TGCC 和 5'-TGTA；ZBM 的 5'-TGCC、5'-TGTA 和 5'-TGCA；以及 BLM 的 5'-TGTA。在纯化的人基因组 DNA 中，DNA 序列偏好为 6'-脱氧 BLM 的 5'-TGTA、ZBM 的 5'-RTGYAYR（其中 R 是 G 或 A）和 BLM 的 5'-TGT*A。因此，6'-脱氧 BLM Z 的 BLM 类似物的序列特异性在纯化的人 DNA 中与 BLM 相似，而 ZBM 则不同。
