Buehl Christopher J, Kuo Min-Hao
Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI, 48824, USA.
Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA.
Curr Genet. 2018 Dec;64(6):1215-1219. doi: 10.1007/s00294-018-0846-4. Epub 2018 May 23.
Biorientation of paired sister chromosomes is required to maintain mitotic fidelity. A critical signal indicative of bipolar attachment is tension between cohesion-linked sister chromatids. Key components of the tension signaling apparatus include the Shugoshin family of proteins and the tension sensing motif of histone H3. Shugoshin proteins are recruited to chromatin to create discrete domains integral to tension sensing. Many factors involved in the chromatin association of Shugoshin proteins are well established, most strikingly through modifications found directly on centromeric and pericentric chromatin. It has been well established that phosphorylation at the centromere is essential to nucleating Shugoshin recruitment, but recent evidence revealed a role for pericentric histones and acetylation in modulating Shugoshin recruitment and activity. These data demonstrate that chromatins are not simply passive cargo during mitosis, but are instead actively involved in their segregation.
配对姐妹染色单体的双定向对于维持有丝分裂的准确性是必需的。表明双极附着的一个关键信号是连接着的姐妹染色单体之间的张力。张力信号传导装置的关键组成部分包括守护蛋白家族和组蛋白H3的张力感应基序。守护蛋白被招募到染色质上，以创建对张力感应不可或缺的离散结构域。许多参与守护蛋白与染色质结合的因素已为人熟知，最显著的是通过在着丝粒和着丝粒周围染色质上直接发现的修饰。已经明确，着丝粒处的磷酸化对于启动守护蛋白的招募至关重要，但最近的证据揭示了着丝粒周围组蛋白和乙酰化在调节守护蛋白招募和活性方面的作用。这些数据表明，染色质在有丝分裂期间并非仅仅是被动的货物，而是积极参与其分离过程。
