Friday, April 11, 2008, 11AM

Bldg. 38A, B2 library 

Artem Novozhilov

Title: Evolution of the genetic code: Partial optimization for robustness to translation errors

Abstract: The standard genetic code table has a distinctly non-random structure, with similar amino acids are often encoded 
by codon series that differ by a single substitution. I will give a short review of the main theories that claim to explain 
the pattern of amino acid assignments. Amongst the most influential theories is the adaptive hypothesis which posits that 
the structure of the code results from selective optimization for robustness to translation errors such that translational 
misreading has the minimal adverse effect. However, it remains unclear how much evolution the standard code underwent, 
what is the level of optimization, and what is the likely starting point. I will present the results of exploration of 
a toy model of the code's evolution in order to determine the place of the standard code in the space of all imaginable 
codes. One of the results is that the standard genetic code appears to be a point on an evolutionary trajectory from 
a random point (code) about half the way to the summit of the local peak on the fitness landscape.