Molecular and Cellular Biochemistry Department, Indiana University, Bloomington, IN, USA; Biology Department, Indiana University, Bloomington, IN, USA.
Molecular and Cellular Biochemistry Department, Indiana University, Bloomington, IN, USA; Biology Department, Indiana University, Bloomington, IN, USA.
Mol Cell. 2021 Feb 4;81(3):473-487.e6. doi: 10.1016/j.molcel.2020.12.001. Epub 2020 Dec 30.
Chromosome conformation capture (3C) technologies have identified topologically associating domains (TADs) and larger A/B compartments as two salient structural features of eukaryotic chromosomes. These structures are sculpted by the combined actions of transcription and structural maintenance of chromosomes (SMC) superfamily proteins. Bacterial chromosomes fold into TAD-like chromosomal interaction domains (CIDs) but do not display A/B compartment-type organization. We reveal that chromosomes of Sulfolobus archaea are organized into CID-like topological domains in addition to previously described larger A/B compartment-type structures. We uncover local rules governing the identity of the topological domains and their boundaries. We also identify long-range loop structures and provide evidence of a hub-like structure that colocalizes genes involved in ribosome biogenesis. In addition to providing high-resolution descriptions of archaeal chromosome architectures, our data provide evidence of multiple modes of organization in prokaryotic chromosomes and yield insights into the evolution of eukaryotic chromosome conformation.
染色质构象捕获（3C）技术已经确定了拓扑关联域（TAD）和更大的 A/B 区室作为真核染色体的两个显著结构特征。这些结构是由转录和染色体结构维持（SMC）超家族蛋白的共同作用塑造的。细菌染色体折叠成类似于 TAD 的染色体相互作用域（CID），但不显示 A/B 区室类型的组织。我们揭示了 Sulfolobus 古菌的染色体除了以前描述的更大的 A/B 区室类型结构外，还被组织成类似于 CID 的拓扑域。我们发现了控制拓扑域身份及其边界的局部规则。我们还鉴定了长距离环结构，并提供了涉及核糖体生物发生的基因聚集在类似枢纽结构中的证据。除了提供对古菌染色体结构的高分辨率描述外，我们的数据还提供了原核染色体中多种组织模式的证据，并深入了解了真核染色体构象的进化。
