Phase separation driven by production of architectural RNA transcripts.
Phase separation driven by production of architectural RNA transcripts.
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由结构 RNA 转录本的产生驱动的相分离。
DOI：
10.1039/c9sm02458a
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发表时间：
2020
期刊：
影响因子：
3.4
通讯作者：
Tetsuro Hirose
中科院分区：
文献类型：
--
作者：
Tetsuya Yamamoto;Tomohiro Yamazaki;Tetsuro Hirose
在这里，我们使用的Flory-Huggins理论的扩展来预测，相分离是由生产的建筑RNA（arcRNA）在DNA位点以恒定的速率。arcRNA分子在核质中扩散，并通过与arcRNA结合的蛋白质显示吸引力相互作用。我们的理论预测，当Flory相互作用参数大于临界点处的值时，arcRNA的体积分数在两个值之间跳跃，这两个值对应于由于局部平衡条件而在距离DNA位点一定距离处处于平衡的两个共存相的体积分数。该距离限定了通过相分离聚集的冷凝物的半径。当相互作用参数较大时，凝聚物的体积与arcRNA的产生速率成正比，与arcRNA的降解速率成反比。这些结果意味着大多数arcRNA分子在它们由于arcRNA的强分离而从浓缩物扩散出来之前被降解。
We here use an extension of the Flory–Huggins theory to predict that phase separation is driven by the production of architectural RNA (arcRNA) at a DNA locus with a constant rate. The arcRNA molecules diffuse in the nucleoplasm and show attractive interactions via proteins that are bound to the arcRNA. Our theory predicts that when the Flory interaction parameter is larger than the value at the critical point, the volume fraction of arcRNA jumps between the two values corresponding to the volume fraction of the two coexisting phases at equilibrium at a distance from the DNA locus due to the local equilibrium condition. The distance defines the radius of the condensate that is assembled by the phase separation. When the interaction parameter is large, the volume of the condensates is proportional to the production rate of arcRNA and inversely proportional to the degradation rate of arcRNA. These results imply that most arcRNA molecules are degraded before they diffuse out from the condensates due to the strong segregation of arcRNA.