Self-description and the origin of the genetic code.
The genetic code presents an important conceptual challenge within the broader context of the origin of life. Translation of genetic information captures a fundamental property of living systems, i.e. the ability of decoding proteins (e.g. aminoacyl-tRNA synthetases) to reproduce themselves from self-contained RNA/DNA descriptors. Silvano Colombano and I, as graduate students with Howard Pattee in the 1970s, focused on achieving this closure of self-description and self-reproduction in the genetic code. Simulation and analysis of competitive models that allowed alternate code assignments, exploring initial conditions, arbitrary descriptor-catalyst relationships, and degree of non-linearity, indicated that these dynamical systems undergo bifurcations, transforming initial ambiguous stable states to unstable states. New, stable, steady states, progressively closer to a code, became available as the descriptor parameters were varied. The efficiency of utilization of raw materials for the production of a coding family of catalysts is proposed as a selection criterion that drives such systems towards a coded state.
Bedian
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Pfizer Global Research & Development, Eastern Point Road, Groton, CT 06340, USA. vahe_bedian@groton.pfizer.com
D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism; D005075:Biological Evolution; D001703:Biophysics / Q000266:history; D005815:Genetic Code; D049673:History, 20th Century; D008954:Models, Biological; D017711:Nonlinear Dynamics; D000069497:Origin of Life
D000604:Amino Acyl-tRNA Synthetases