Liquid Crystal Coacervates Composed of Short Double Stranded DNA and Cationic Peptides.
Liquid Crystal Coacervates Composed of Short Double Stranded DNA and Cationic Peptides.
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DOI：
10.26434/chemrxiv.12220418
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发表时间：
2020-04
期刊：
影响因子：
17.1
通讯作者：
T. P. Fraccia;Tony Z. Jia
中科院分区：
文献类型：
--
作者：
T. P. Fraccia;Tony Z. Jia
核酸和蛋白质的相分离是调节亚细胞区室结构和功能的普遍现象。虽然柔性单链核酸的复合凝聚被广泛研究，但双链DNA（dsDNA）的凝聚由于其产生固体沉淀物的倾向而较少研究。在这里，我们扭转了这一观点，表明短dsDNA和多聚L-赖氨酸凝聚层可以逃脱沉淀，同时显示出令人惊讶的复杂相图，包括迄今为止在大量dsDNA中观察到的全套液晶（LC）中间相。短链双链DNA在凝聚相中的超分子聚集和堆积是控制整个LC-凝聚相行为的主要参数。LC-凝聚层结构的特征在于温度和单价盐，DNA和肽浓度的变化，这允许所有可接近的相之间的连续可逆转变。更深入地了解LC凝聚体可以获得洞察力，以破译生物分子凝聚体中的结构和相变机制，设计具有不同有序度的刺激响应多相合成隔室，并利用自组装驱动的核酸和肽的合作益生元进化。
Phase separation of nucleic acids and proteins is a ubiquitous phenomenon regulating sub-cellular compartment structure and function. While complex coacervation of flexible single stranded nucleic acids is broadly investigated, coacervation of double stranded DNA (dsDNA) is less studied because of its propensity to generate solid precipitates. Here, we reverse this perspective by showing that short dsDNA and poly-L-lysine coacervates can escape precipitation while displaying a surprisingly complex phase diagram, including the full set of liquid crystal (LC) mesophases observed to date in bulk dsDNA. Short dsDNA supramolecular aggregation and packing in the dense coacervate phase are the main parameters regulating the global LC-coacervate phase behavior. LC-coacervate structure was characterized upon variations in temperature and monovalent salt, DNA and peptide concentrations, which allow continuous reversible transitions between all accessible phases. A deeper understanding of LC-coacervates can gain insights to decipher structures and phase transition mechanisms within biomolecular condensates, to design stimuli-responsive multi-phase synthetic compartments with different degrees of order and to exploit self-assembly driven cooperative prebiotic evolution of nucleic acids and peptides.