Bryant Gene O
Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Methods Mol Biol. 2012;833:47-61. doi: 10.1007/978-1-61779-477-3_4.
Eukaryotic genomes are wrapped in nucleosomes. These nucleosomes could be a barrier or could help facilitate the binding of transcription or replication factors. To understand what biological role nucleosomes play, an accurate and reliable method for measuring not only the position of a nucleosome but the fraction of the population that is bound by a nucleosome is needed. Here is described a method for determining nucleosome occupancy that takes advantage of the difference in the rate of digestion of DNA by micrococcal nuclease when naked DNA is compared to the same DNA bound by a nucleosome. Curve fitting to a function that describes the amount of DNA remaining following a series of digestions over a broad range of micrococcal nuclease allows the calculation of nucleosome occupancy anywhere in the genome under many different conditions in vivo.
真核生物基因组包裹在核小体中。这些核小体可能是一种障碍，也可能有助于促进转录或复制因子的结合。为了了解核小体发挥何种生物学作用，需要一种准确可靠的方法，不仅要测量核小体的位置，还要测量被核小体结合的群体比例。本文描述了一种确定核小体占有率的方法，该方法利用了与被核小体结合的相同DNA相比，微球菌核酸酶对裸露DNA的消化速率差异。通过对一个描述在广泛的微球菌核酸酶作用下一系列消化后剩余DNA量的函数进行曲线拟合，可以计算出在体内许多不同条件下基因组中任何位置的核小体占有率。
