Liquid–liquid phase separation has been shown to underlie the formation and disassembly of membraneless organelles in cells, but the cellular mechanisms that control this phenomenon are poorly understood. A prominent example of regulated and reversible segregation of liquid phases may occur during mitosis, when membraneless organelles disappear upon nuclear-envelope breakdown and reappear as mitosis is completed. Here we show that the dual-specificity kinase DYRK3 acts as a central dissolvase of several types of membraneless organelle during mitosis. DYRK3 kinase activity is essential to prevent the unmixing of the mitotic cytoplasm into aberrant liquid-like hybrid organelles and the over-nucleation of spindle bodies. Our work supports a mechanism in which the dilution of phase-separating proteins during nuclear-envelope breakdown and the DYRK3-dependent degree of their solubility combine to allow cells to dissolve and condense several membraneless organelles during mitosis.The dual-specificity kinase DYRK3 acts as a central ‘dissolvase’, mediating the phase transitions of several types of membraneless organelles during mitosis.

中文翻译：

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有丝分裂中无膜细胞器激酶控制的相变

液-液相分离已被证明是细胞中无膜细胞器形成和分解的基础，但控制这种现象的细胞机制知之甚少。在有丝分裂过程中可能发生液相的受调控和可逆分离的一个突出例子，当核膜破裂时无膜细胞器消失，并在有丝分裂完成时重新出现。在这里，我们表明双特异性激酶 DYRK3 在有丝分裂过程中充当几种类型无膜细胞器的中枢溶解酶。DYRK3 激酶活性对于防止有丝分裂细胞质分离成异常的液体样混合细胞器和纺锤体过度成核至关重要。