TBI 02-08-034
On the Evolution of Primitive Genetic Codes
02-08-034
Abstract:
On the Evolution of Primitive Genetic Codes
[PostScript]
[PDF]
Günter Weberndorfer, Ivo L. Hofacker, Peter F. Stadler
The primordial genetic code probably has been a drastically simplified
ancestor of the canonical code that is used by contemporary cells. In order
to understand how the present-day code came about we first need to explain
how the language of the building plan can change without destroying the
encoded information. In this work we introduce a minimal organism model
that is based on biophysically reasonable descriptions of RNA and protein,
namely secondary structure folding and knowledge based potentials. The
evolution of a population of such an organism under competition for a common
resource is simulated explicitly at the level of individual replication
events. Starting with very simple codes, and hence greatly reduced amino
acid alphabets, we observe a diversification of the codes in most
simulation runs. The driving force behind this effect is the possibility
of producing fitter proteins when the repertoire of amino acids is enlarged.
Keywords:
Genetic Code, Evolution, Minimal Organism, Tank Reactor
Return to 2002 working papers list.