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 compositional 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.

中文翻译：

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核中染色质的中尺度相分离

果蝇幼虫的完整生物成像揭示并定量染色质-水相分离。染色质可以组织在核被膜的薄层附近，通常填充核，在中心组织，或作为润湿液滴。这些过渡受核体积的变化以及染色质与核外围的层板（核包膜的一部分）的相互作用控制。使用一个简单的聚合物模型，其中包括染色质自吸引的关键特征及其与薄片的结合，我们在理论上证明了这两种效应的竞争决定了染色质分布的模式。在我们的模拟中获得的定性趋势以及组成图谱与观察到的完整有机体成像和定量结果相比具有很好的对比性。