Russian Journal of Genetics

, Volume 46, Issue 8, pp 899–916

Expanding genetic code: Amino acids 21 and 22, selenocysteine and pyrrolysine

Reviews and Theoretical Articles

DOI: 10.1134/S1022795410080016

Cite this article as:
Lukashenko, N.P. Russ J Genet (2010) 46: 899. doi:10.1134/S1022795410080016


The discovery of two atypical amino acids, selenocysteine and pyrrolysine, in the genetic code is discussed. These findings have expanded our understanding of the genetic code, since the repertoire of amino acids in the genetic code was supplemented by two novel ones, in addition of the standard 20 amino acids. Current views on specific mechanisms of selenocysteine insertion in forming selenoproteins are considered, as well as the results of studies of new translational components involved in biosynthesis and incorporation of selenocysteine at different stages of translation. Similarity in the strategies of decoding UGA and UAG as codons for respectively selenocysteine and pyrrolysine is discussed. The review also presents evidence on the medical and biological role of selenium and selenoproteins containing selenocysteine as the main biological form of selenium.

Copyright information

© Pleiades Publishing, Ltd. 2010

Authors and Affiliations

  1. 1.Vavilov Institute of General GeneticsRussian Academy of SciencesMoscowRussia