论文标题
通过环状相分离选择益生元寡核苷酸
Selection of prebiotic oligonucleotides by cyclic phase separation
论文作者
论文摘要
功能性寡核苷酸在地球早期的出现需要一种分子选择机制，以筛选具有益生元功能的特定序列。在这种环境中，循环过程（例如每日温度振荡）无处不在，并可能触发寡核苷酸相分离。在这里，我们提出了基于通过沉积的相位分离周期在接受寡核苷酸进食的系统中实现的序列选择。使用DNA的理论和实验，我们显示了沉积物的序列特异性富集，特别是在短22-Mer DNA序列中。基本机制选择了互补性，因为它丰富了通过碱基对在凝结相中紧密相互作用的序列。我们的机制还使最初较弱的偏置池能够增强其序列偏差或随着循环的进展而取代最丰富的序列。我们的发现提供了一种选择机制的示例，该机制可能会简化第一次自动催化自我复制寡核苷酸的筛查。
The emergence of functional oligonucleotides on early Earth required a molecular selection mechanism to screen for specific sequences with prebiotic functions. Cyclic processes such as daily temperature oscillations were ubiquitous in this environment and could trigger oligonucleotide phase separation. Here, we propose sequence selection based on phase separation cycles realized through sedimentation in a system subjected to the feeding of oligonucleotides. Using theory and experiments with DNA, we show sequence-specific enrichment in the sedimented dense phase, in particular of short 22-mer DNA sequences. The underlying mechanism selects for complementarity, as it enriches sequences that tightly interact in the condensed phase through base-pairing. Our mechanism also enables initially weakly biased pools to enhance their sequence bias or to replace the most abundant sequences as the cycles progress. Our findings provide an example of a selection mechanism that may have eased screening for the first auto-catalytic self-replicating oligonucleotides.
