Laboratory for Developmental Epigenetics, RIKEN Center for Biosystems Dynamics Research (BDR), 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047 Japan.
Laboratory for Developmental Epigenetics, RIKEN Center for Biosystems Dynamics Research (BDR), 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047 Japan.
Curr Opin Cell Biol. 2024 Oct;90:102406. doi: 10.1016/j.ceb.2024.102406. Epub 2024 Jul 30.
Mammalian chromosomes form a hierarchical structure within the cell nucleus, from chromatin loops, megabase (Mb)-sized topologically associating domains (TADs) to larger-scale A/B compartments. The molecular basis of the structures of loops and TADs has been actively studied. However, the A and B compartments, which correspond to early-replicating euchromatin and late-replicating heterochromatin, respectively, are still relatively unexplored. In this review, we focus on the A/B compartments, discuss their close relationship to DNA replication timing (RT), and introduce recent findings on the features of subcompartments revealed by detailed classification of the A/B compartments. In doing so, we speculate on the structure, potential function, and developmental dynamics of A/B compartments and subcompartments in mammalian cells.
哺乳动物染色体在细胞核内形成一个层次结构，从染色质环、兆碱基（Mb）大小的拓扑关联域（TAD）到更大尺度的 A/B 区室。环和 TAD 的结构的分子基础已被积极研究。然而，A 和 B 区室分别对应于早期复制的常染色质和晚期复制的异染色质，仍然相对没有被探索。在这篇综述中，我们专注于 A/B 区室，讨论它们与 DNA 复制时间（RT）的密切关系，并介绍最近关于通过对 A/B 区室进行详细分类揭示的亚区室特征的发现。这样做的同时，我们推测了哺乳动物细胞中 A/B 区室和亚区室的结构、潜在功能和发育动态。
