Center for Evolutionary Medicine and Informatics in the Biodesign Institute and Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-5301, USA.
Nat Chem. 2012 Jan 10;4(3):183-7. doi: 10.1038/nchem.1241.
The pre-RNA world hypothesis postulates that RNA was preceded in the evolution of life by a simpler genetic material, but it is not known if such systems can fold into structures capable of eliciting a desired function. Presumably, whatever chemistry gave rise to RNA would have produced other RNA analogues, some of which may have preceded or competed directly with RNA. Threose nucleic acid (TNA), a potentially natural derivative of RNA, has received considerable interest as a possible RNA progenitor due to its chemical simplicity and ability to exchange genetic information with itself and RNA. Here, we have applied Darwinian evolution methods to evolve, in vitro, a TNA receptor that binds to an arbitrary target with high affinity and specificity. This demonstration shows that TNA has the ability to fold into tertiary structures with sophisticated chemical functions, which provides evidence that TNA could have served as an ancestral genetic system during an early stage of life.
前 RNA 世界假说假设，在生命进化过程中，RNA 之前存在一种更简单的遗传物质，但目前尚不清楚这些系统是否能够折叠成具有所需功能的结构。可以推测，任何产生 RNA 的化学物质都会产生其他 RNA 类似物，其中一些可能早于或直接与 RNA 竞争。作为 RNA 的潜在天然衍生物，三碳核酸 (TNA) 因其化学简单性以及与自身和 RNA 交换遗传信息的能力而受到相当多的关注，被认为是可能的 RNA 前体。在这里，我们应用达尔文进化方法，在体外进化出一种 TNA 受体，该受体能够高亲和力和特异性地结合任意靶标。这一证明表明，TNA 具有折叠成具有复杂化学功能的三级结构的能力，这为 TNA 可能在生命早期作为一种祖先遗传系统提供了证据。
