美国印第安纳大学Stephen D. Bell研究团队发现古生菌染色体的结构和功能分区。这一研究成果于2019年9月19日发表在《细胞》杂志上。

他们描述了硫化叶菌的染色体构象捕获实验。这些揭示了随着硫化叶菌染色体存在不同的结构域，这些结构域经历离散的和特定的高阶相互作用，因此限定了两个区室类型。他们观察到隔室特性，基因表达和迄今未鉴定的（高阶结构依赖于染色体）SMC超家族蛋白（我们称之为“聚结蛋白”）的结合之间的因果联系。

据悉，染色体的三维组织可以对它们的复制和表达产生深远的影响。高等真核生物的染色体具有离散的区室，其特征在于不同的转录活性。相比之下，大多数细菌染色体具有更简单的组织，具有局部结构域，其边界受基因表达的影响。大量研究表明，细菌和真核染色体高度有序结构维持依赖于SMC超家族蛋白复合物，特别是近通用的缩合蛋白复合物。然而，有趣的是，许多古生菌，包括硫化叶菌属的成员不编码经典凝聚素。

附：英文原文

Title: Physical and Functional Compartmentalization of Archaeal Chromosomes

Author: Naomichi Takemata, Rachel Y. Samson, Stephen D. Bell

Issue&Volume: Volume 179 Issue 1

Summary: 

The three-dimensional organization of chromosomes can have a profound impact on their replication and expression. The chromosomes of higher eukaryotes possess discrete compartments that are characterized by differing transcriptional activities. Contrastingly, most bacterial chromosomes have simpler organization with local domains, the boundaries of which are influenced by gene expression. Numerous studies have revealed that the higher-order architectures of bacterial and eukaryotic chromosomes are dependent on the actions of structural maintenance of chromosomes (SMC) superfamily protein complexes, in particular, the near-universal condensin complex. Intriguingly, however, many archaea, including members of the genus Sulfolobus do not encode canonical condensin. We describe chromosome conformation capture experiments on Sulfolobus species. These reveal the presence of distinct domains along Sulfolobus chromosomes that undergo discrete and specific higher-order interactions, thus defining two compartment types. We observe causal linkages between compartment identity, gene expression, and binding of a hitherto uncharacterized SMC superfamily protein that we term “coalescin.”

DOI: 10.1016/j.cell.2019.08.036

Source: https://www.cell.com/cell/fulltext/S0092-8674(19)30955-9