Abstract: |
The genetic code and genetic evolution are at the core of complexity in biology, however, there is no reasonable
explanation yet for the emergence of the genetic code. We present here a possible scenario accounting for the
emergence of “coded life” in nature: We describe the emergence of the genetic code from molecular evolution,
prior to genetic evolution, in a chemical era in which all the molecules were still located within (probably
non-biological) compartments. Our scenario is obtained by combining the conceptual idea of “code-prompting
autocatalytic sets” (Agmon and Mor, 2015), with recent results about non-enzymatic template replication
methods (Prywes et al, 2016), possibly relevant to the prebiotic stage preceding RNA-world. In the scenario
described here, we often use computer science viewpoint and abstraction: We consider sets of strings composed
of letters, such that each letter represents a molecular building block—mainly nucleotides and amino acids,
and each string represents a more complex molecule which is some concatenation of the simpler molecules
represented by letters; the biochemical rules are described in an abstract language of rules and statistics of
letters and strings. We then suggest a novel path, containing several phases, for the emergence of “coded life”. |