Mesoscale phase separation of chromatin in the nucleus.
Mesoscale phase separation of chromatin in the nucleus.
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DOI：
10.7554/elife.63976
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发表时间：
2021-05-04
期刊：
影响因子：
7.7
通讯作者：
Safran S
中科院分区：
文献类型：
--
作者：
Bajpai G;Amiad Pavlov D;Lorber D;Volk T;Safran S
果蝇幼虫的完整有机体成像揭示和量化染色质-水相分离。染色质可以组织在核被膜的板层附近，通常填充细胞核，组织在中央，或作为润湿液滴。这些转变是由核体积的变化和染色质与核周围的纤层（核被膜的一部分）的相互作用控制的。使用一个简单的聚合物模型，其中包括染色质的自吸引力和它的结合到薄层的关键功能，我们从理论上证明，这是这两种影响的竞争，决定了染色质分布的模式。定性的趋势，以及在我们的模拟中获得的组合物配置文件比较以及与所观察到的完整的生物体成像和定量。由于模拟只包含少量的物理变量，我们可以确定所观察到的相分离的变化背后的一般机制。
Intact-organism imaging of Drosophila larvae reveals and quantifies chromatin-aqueous phase separation. The chromatin can be organized near the lamina layer of the nuclear envelope, conventionally fill the nucleus, be organized centrally, or as a wetting droplet. These transitions are controlled by changes in nuclear volume and the interaction of chromatin with the lamina (part of the nuclear envelope) at the nuclear periphery. Using a simple polymeric model that includes the key features of chromatin self-attraction and its binding to the lamina, we demonstrate theoretically that it is the competition of these two effects that determines the mode of chromatin distribution. The qualitative trends as well as the composition profiles obtained in our simulations compare well with the observed intact-organism imaging and quantification. Since the simulations contain only a small number of physical variables we can identify the generic mechanisms underlying the changes in the observed phase separations.