Platt James L, Kent Nick A, Harwood Adrian J, Kimmel Alan R
Laboratory of Cellular and Developmental Biology, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA.
Methods Mol Biol. 2013;983:173-83. doi: 10.1007/978-1-62703-302-2_9.
Micrococcal nuclease (MNase) is an endonuclease that cleaves native DNA at high frequency, but is blocked in chromatin by sites of intimate DNA-protein interaction, including nucleosomal regions. Protection from MNase cleavage has often been used to map transcription factor binding sites and nucleosomal positions on a single-gene basis; however, by combining MNase digestion with high--throughput, paired-end DNA sequencing, it is now possible to simultaneously map DNA-protein interaction regions across the entire genome. Biochemical and bioinformatic protocols are detailed for global mono-nucleosome positioning at ~160 bp spacing coverage, but are applicable to mapping more broadly or for site-specific binding of transcription factors at ~50 bp resolution.
微球菌核酸酶(MNase)是一种核酸内切酶,它能高频切割天然DNA,但在染色质中会被紧密的DNA-蛋白质相互作用位点(包括核小体区域)所阻断。利用对MNase切割的抗性常被用于在单基因基础上绘制转录因子结合位点和核小体位置;然而,通过将MNase消化与高通量、双末端DNA测序相结合,现在有可能在全基因组范围内同时绘制DNA-蛋白质相互作用区域。本文详细介绍了生化和生物信息学方案,用于在约160 bp间距覆盖范围内进行全基因组单核小体定位,但也适用于更广泛的图谱绘制或在约50 bp分辨率下绘制转录因子的位点特异性结合图谱。