Evolution and RNA Relics. A Systems Biology View

Jacques Demongeot (1, 2) , Nicolas Glade (1) , Andres Moreira (3)

1 AGIM - AGeing and IMagery
2 IXXI - Institut Rhône-Alpin des systèmes complexes
3 Departamento de Matematica [Valparaiso]

The genetic code has evolved from its initial non-degenerate wobble version until reaching its present state of degeneracy. By using the stereochemical hypothesis, we revisit the problem of codon assignations to the synonymy classes of amino-acids. We obtain these classes with a simple classifier based on physico-chemical properties of nucleic bases, like hydrophobicity and molecular weight. Then we propose simple RNA (or more generally XNA, with X for D, P or R) ring structures that present, overlap included, one and only one codon by synonymy class as solutions of a combinatory variational problem. We compare these solutions to sequences of present RNAs considered as relics, with a high interspecific invariance, like invariant parts of tRNAs and micro-RNAs. We conclude by emphasizing some optimal properties of the genetic code.

Mots clés: Genetic code; Primitive RNA; Archetypal RNA ring; RNA relics; Micro-RNA; siRNA

Domaines: Génomique, Transcriptomique et Protéomique [q-bio.GN]; Evolution [q-bio.PE]

Jacques Demongeot, Nicolas Glade, Andres Moreira. Evolution and RNA Relics. A Systems Biology View. Acta Biotheoretica, 2008, 56, pp.5. ⟨10.1007/s10441-008-9028-y⟩. ⟨hal-00724905⟩