The dawn of the RNA World: toward functional complexity through ligation of random RNA oligomers

RNA. 2009 May;15(5):743-9. doi: 10.1261/rna.1488609. Epub 2009 Mar 24.


A main unsolved problem in the RNA World scenario for the origin of life is how a template-dependent RNA polymerase ribozyme emerged from short RNA oligomers obtained by random polymerization on mineral surfaces. A number of computational studies have shown that the structural repertoire yielded by that process is dominated by topologically simple structures, notably hairpin-like ones. A fraction of these could display RNA ligase activity and catalyze the assembly of larger, eventually functional RNA molecules retaining their previous modular structure: molecular complexity increases but template replication is absent. This allows us to build up a stepwise model of ligation-based, modular evolution that could pave the way to the emergence of a ribozyme with RNA replicase activity, step at which information-driven Darwinian evolution would be triggered.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Evolution, Molecular*
  • Inverted Repeat Sequences
  • Nucleic Acid Conformation
  • Origin of Life
  • RNA, Catalytic / chemistry
  • RNA, Catalytic / genetics*
  • RNA, Catalytic / metabolism


  • RNA, Catalytic