The inner centromere is a region on the mitotic chromosome that serves as a platform for mitotic signaling and possesses unique biophysical properties that enable it to withstand relatively large pulling forces that are generated by kinetochores (KTs) during chromosome segregation. The chromosomal passenger complex (CPC) localizes to and is the key regulator of inner centromere organization and function during mitosis. Recently, we demonstrated that in addition to its kinase and histone code-reading activities, the CPC also can undergo liquid–liquid phase separation (LLPS) and proposed that the inner centromere is a membraneless organelle scaffolded by the CPC. In this perspective, we explore mechanisms that can allow the formation and dissolution of this membraneless body. The cell-cycle-regulated spatially defined assembly and disassembly of the CPC condensate at the inner centromere can reveal general principles about how histone modifications control chromatin-bound membraneless organelles. We further explore how the ability of the CPC to undergo LLPS may contribute to the organization and function of the inner centromere during mitosis.

内部着丝粒是有丝分裂染色体上的一个区域，作为有丝分裂信号传导的平台，并具有独特的生物物理特性，使其能够承受染色体分离过程中着丝粒 (KT) 产生的相对较大的拉力。染色体乘客复合体 (CPC) 位于有丝分裂过程中，是内部着丝粒组织和功能的关键调节者。最近，我们证明除了其激酶和组蛋白代码读取活性外，CPC还可以进行液-液相分离（LLPS），并提出内部着丝粒是由CPC支架的无膜细胞器。从这个角度来看，我们探索了这种无膜体形成和溶解的机制。细胞周期调节的内部着丝粒 CPC 凝聚物的空间限定组装和分解可以揭示组蛋白修饰如何控制染色质结合的无膜细胞器的一般原理。我们进一步探讨了 CPC 进行 LLPS 的能力如何有助于有丝分裂期间内部着丝粒的组织和功能。