Graduate Program in Biophysics, Harvard University, Cambridge, MA, United States.
Curr Opin Genet Dev. 2012 Apr;22(2):115-24. doi: 10.1016/j.gde.2012.01.006. Epub 2012 Feb 22.
Advances in microscopy and genomic techniques have provided new insight into spatial chromatin organization inside of the nucleus. In particular, chromosome conformation capture data has highlighted the relevance of polymer physics for high-order chromatin organization. In this context, we review basic polymer states, discuss how an appropriate polymer model can be determined from experimental data, and examine the success and limitations of various polymer models of higher-order interphase chromatin organization. By taking into account topological constraints acting on the chromatin fiber, recently developed polymer models of interphase chromatin can reproduce the observed scaling of distances between genomic loci, chromosomal territories, and probabilities of contacts between loci measured by chromosome conformation capture methods. Polymer models provide a framework for the interpretation of experimental data as ensembles of conformations rather than collections of loops, and will be crucial for untangling functional implications of chromosomal organization.
显微镜技术和基因组技术的进步为核内空间染色质组织提供了新的见解。特别是，染色体构象捕获数据强调了高分子物理对于高级染色质组织的重要性。在这种情况下，我们回顾了基本的聚合物状态，讨论了如何从实验数据中确定合适的聚合物模型，并研究了各种高级相间染色质组织的聚合物模型的成功和局限性。通过考虑作用在染色质纤维上的拓扑约束，最近开发的相间染色质聚合物模型可以再现通过染色体构象捕获方法测量的基因组位点、染色体区域之间的距离以及位点之间接触概率的观察到的标度。聚合物模型为解释实验数据提供了一个框架，即将其作为构象的集合而不是环的集合，对于梳理染色体组织的功能意义至关重要。
