Tripartite Chromatin Localization of Budding Yeast Shugoshin Involves Higher-Ordered Architecture of Mitotic Chromosomes

G3: Genes, Genomes, Genetics

Xiexiong Deng^1¹ 

[1] Department of Biochemistry and Molecular Biology, Michigan State University. East Lansing, MI 48824^1

关键词: Saccharomyces cerevisiae;    spindle assembly checkpoint;    Shugoshin;    histone H3;    tension sensing;   

DOI  :  10.1534/g3.118.200522

学科分类：生物科学（综合）

来源: Genetics Society of America

【 摘 要 】

The spindle assembly checkpoint (SAC) is key to faithful segregation of chromosomes. One requirement that satisfies SAC is appropriate tension between sister chromatids at the metaphase-anaphase juncture. Proper tension generated by poleward pulling of mitotic spindles signals biorientation of the underlying chromosome. In the budding yeast, the tension status is monitored by the conserved Shugoshin protein, Sgo1p , and the tension sensing motif (TSM) of histone H3. ChIP-seq reveals a unique TSM-dependent, tripartite domain of Sgo1p in each mitotic chromosome. This domain consists of one centromeric and two flanking peaks 3 – 4 kb away, present exclusively in mitosis. Strikingly, this trident motif coincides with cohesin localization, but only at the centromere and the two immediate adjacent loci, despite that cohesin is enriched at numerous regions throughout mitotic chromosomes. Chromosome conformation capture assays reveal apparent looping at the centromeric and pericentric regions. The TSM- Sgo1p -cohesin triad is therefore at the center stage of higher-ordered chromatin architecture for error-free segregation.

【 授权许可】

CC BY