Biological Theory

, Volume 10, Issue 4, pp 301–310

Evolution of the Genetic Code: The Ribosome-Oriented Model

Original Article

DOI: 10.1007/s13752-015-0225-z

Cite this article as:
Barbieri, M. Biol Theory (2015) 10: 301. doi:10.1007/s13752-015-0225-z

Abstract

There are currently three major theories on the origin and evolution of the genetic code: the stereochemical theory, the coevolution theory, and the error-minimization theory. The first two assume that the genetic code originated respectively from chemical affinities and from metabolic relationships between codons and amino acids. The error-minimization theory maintains that in primitive systems the apparatus of protein synthesis was extremely prone to errors, and postulates that the genetic code evolved in order to minimize the deleterious effects of the translation errors. This article describes a fourth theory which starts from the hypothesis that the ancestral genetic code was ambiguous and proposes that its evolution took place with a mechanism that systematically reduced its ambiguity and eventually removed it altogether. This proposal is distinct from the stereochemical and the coevolution theories because they do not contemplate any ambiguity in the genetic code, and it is distinct from the error-minimization theory because ambiguity-reduction is fundamentally different from error-minimization. The concept of ambiguity-reduction has been repeatedly mentioned in the scientific literature, but so far it has remained only an abstract possibility because no model has been proposed for its mechanism. Such a model is described in the present article and may be the first step in a new approach to the study of the evolution of the genetic code.

Keywords

Code ambiguity Code evolution Codepoiesis Genetic code Ribosomal proteins Ribosomes 

Copyright information

© Konrad Lorenz Institute for Evolution and Cognition Research 2015

Authors and Affiliations

  1. 1.Department of Morphology and EmbryologyUniversity of FerraraFerraraItaly