RNA以前に非環状型XNAがPre-RNAとして存在したか？

抄録

  We have developed artificial acyclic nucleic acids composed of serinol derivatives as scaffolds. Recently, template-directed synthesis of acyclic L-threoninol nucleic acid (L-αTNA) could be achieved non-enzymatically via chemical ligation mediated by N-cyanoimidazole in the presence of Mn²⁺ ion. A pseudo primer extension reaction like natural polymerase was also attained non-enzymatically using a pool of random L-αTNA trimers. In this short review, we discuss the possibility of L-αTNA as a candiate of pre-RNA before RNA world by focusing on the evolution of genetic material.