近日，英国爱丁堡大学Adele L. Marston及其团队发现，收敛基因塑造芽殖酵母的近着丝粒。这一研究成果于2020年4月29日发表在国际学术期刊《自然》上。
研究人员报道了芽殖酵母（酿酒酵母）中的着丝粒的三维结构，并建立了基因组组织和功能之间的关系。研究人员发现收敛基因标记着丝粒边界，并与核心着丝粒一起通过定位cohesin来定义它们的结构和功能。着丝粒负载cohesin，而着丝粒边界处的收敛基因将其捕获。着丝粒的每一侧都被组织成环状构象，而边界融合基因位于基部。
微管附件延伸单个着丝粒环，其大小受其边界处的收敛基因限制。将边界处的基因重新定向为串联构型可重新定位cohesin，进而扩大了着丝粒，并在有丝分裂期间损害了染色体的生物定向。因此，转录单位的线性排列与靶向cohesin的加载一起将着丝粒形成可胜任染色体分离的结构。这些研究结果揭示了嵌入动植物染色体区域的结构，以及由微管附着引起的重组。此外，还建立了特定染色体结构域的三维基因组组织与细胞功能之间的直接因果关系。
据介绍，基因组的三维结构控制着其维持、表达和传播。cohesin蛋白复合物通过拓扑连接遥远的基因座来组织基因组，并且高度富集于着丝粒周围的专门染色体结构域，称为近着丝粒。
附：英文原文
Title: Convergent genes shape budding yeast pericentromeres
Author: Flora Paldi, Bonnie Alver, Daniel Robertson, Stephanie A. Schalbetter, Alastair Kerr, David A. Kelly, Jonathan Baxter, Matthew J. Neale, Adele L. Marston
Issue&Volume: 2020-04-29
Abstract: The three-dimensional architecture of the genome governs its maintenance, expression and transmission. The cohesin protein complex organizes the genome by topologically linking distant loci, and is highly enriched in specialized chromosomal domains surrounding centromeres, called pericentromeres1,2,3,4,5,6. Here we report the three-dimensional structure of pericentromeres in budding yeast (Saccharomyces cerevisiae) and establish the relationship between genome organization and function. We find that convergent genes mark pericentromere borders and, together with core centromeres, define their structure and function by positioning cohesin. Centromeres load cohesin, and convergent genes at pericentromere borders trap it. Each side of the pericentromere is organized into a looped conformation, with border convergent genes at the base. Microtubule attachment extends a single pericentromere loop, size-limited by convergent genes at its borders. Reorienting genes at borders into a tandem configuration repositions cohesin, enlarges the pericentromere and impairs chromosome biorientation during mitosis. Thus, the linear arrangement of transcriptional units together with targeted cohesin loading shapes pericentromeres into a structure that is competent for chromosome segregation. Our results reveal the architecture of the chromosomal region within which kinetochores are embedded, as well as the restructuring caused by microtubule attachment. Furthermore, we establish a direct, causal relationship between the three-dimensional genome organization of a specific chromosomal domain and cellular function.
DOI: 10.1038/s41586-020-2244-6
Source: https://www.nature.com/articles/s41586-020-2244-6
Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html
本期文章：《自然》：Online/在线发表
