染色质相互作用研究进展

真核生物的染色体如何发生复杂构象变化并组织成复杂的高级结构,仍是一个研究热点。染色体的这些结构特征和构象变化可通过了解染色质位点间的相互作用,即利用染色体（质）构象捕获（3C）及其衍生技术,如4C、5C、Hi-C和ChIA-PET等技术来研究。利用这些技术,已得到一些有关染色质相互作用与基因表达调控和细胞核内染色体组织结构的重要信息。如利用ChIA-PET技术,发现雌激素受体、RNA聚合酶Ⅱ、CTCF等一些转录因子都参与了染色质的长程相互作用,并同时在基因组水平鉴定了特定细胞中的一些相应的有调控潜能的DNA元件及其可能的调控基因。利用Hi-C及其他3C衍生技术,不但表明染色体在细胞核内占据着不同的染色体领域,而且发现染色体上有次级结构域如染色体区隔和染色体拓扑联合域。随着相关技术的完善和更多数据的获得,分析和整合这些数据将对生物信息学家提出更高的要求,同时也可以帮助我们更进一步了解染色体三维构象变化在不同环境下的变化规律,以及在基因转录调控、DNA复制和修复等重要过程中的作用。

Advances in chromatin in teraction studies

How the chromosomes are organized and how the conformation changes affect genome activities are still not fully understood.The chromosome conformation capture（ 3C） techniques,including 3C,4C（ circular3 C or 3C-on-Chip）,5C（ Chromosome Conformation Capture Carbon Copy）,ChIA-PET（ Chromatin Interaction Analysis by Paired-End Tag sequencing）,and Hi-C can be used to explore these long standing questions.With ChIA-PET technique,the De novo enhancer-promoter interactions mediated by estrogen receptor α（ ERα）,RNA polymerase Ⅱand CTCF have been identified in different systems.Subsequently,more general chromatin interactions of all-in-all manner have been obtained with Hi-C method.The results indicate that chromosomes are located in different chromosome territories in nuclei,and further distributed in chromosome compartments,where groups of topologically associated domains are located.More interaction data will be available with the application and improvement of such 3C techniques.It is highly expected to see more detailed images about the organization of genome,during gene regulation,DNA duplication and DNA repair in the near future.