An Inorganic Biopolymer Polyphosphate Controls Positively Charged Protein Phase Transitions
An Inorganic Biopolymer Polyphosphate Controls Positively Charged Protein Phase Transitions
复制标题
无机生物聚合物聚磷酸盐控制带正电荷的蛋白质相变
DOI：
10.1002/anie.201913833
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Zhao Jing
中科院分区：
文献类型：
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作者：
Wang Xin;Shi Chenke;Mo Jianbin;Xu Yun;Wei Wei;Zhao Jing
聚磷酸盐(Polyp)是一种结构最致密的无机多阴离子生物聚合物，参与多种生理过程。然而，息肉与蛋白质相互作用的机制仍不清楚。在这里，我们报道了息肉可以与带正电的绿色荧光蛋白+36GFP相互作用，通过细胞内分子间的静电相互作用导致液-液相分离(LLP)。在营养缺乏的情况下，基因工程弗劳迪柠檬酸杆菌以2 10 μ−1的速率积累胞内息肉，导致细胞极点+36GFP在1 h内隔室。中链长度的息肉(60mer)在 体外可以诱导+36GFP凝聚体的形成，蛋白质浓度低至2 0 0 nm，与天然蛋白的大小相同。相反，在相同条件下，较短的息肉(14聚体)不能诱导LLP。这可能提供了一种通过LLP操纵蛋白质-蛋白质相互作用的一般方法。
Polyphosphate (PolyP) is one of the most compact inorganic polyanionic biopolymers that participates in various physiological processes. However, the mechanism of the interaction between polyP and proteins remains poorly understood. Herein, we report that polyP can interact with positively charged green fluorescent protein, +36GFP, resulting in liquid–liquid phase separation (LLPS) by intermolecular electrostatic interactions in cells. Upon nutrient deprivation, genetically engineered Citrobacter freundii accumulates intracellular polyP at a rate of 210 μmmin−1, resulting in the compartmentation of +36GFP at the cell poles within 1 h. Medium chain‐length polyP (60‐mer) could induce the formation of +36GFP coacervates in vitro at a protein concentration as low as 200 nm, which is of the same magnitude as native proteins. In contrast, shorter polyP (14‐mer) could not induce LLPS under the same conditions. This may offer a general approach to manipulate protein–protein interactions through LLPS.