The Coevolution of Genes and Genetic Codes: Crick’s Frozen Accident Revisited
The standard genetic code is the nearly universal system for the translation of genes into proteins. The code exhibits two salient structural characteristics: it possesses a distinct organization that makes it extremely robust to errors in replication and translation, and it is highly redundant. The origin of these properties has intrigued researchers since the code was first discovered. One suggestion, which is the subject of this review, is that the code’s organization is the outcome of the coevolution of genes and genetic codes. In 1968, Francis Crick explored the possible implications of coevolution at different stages of code evolution. Although he argues that coevolution was likely to influence the evolution of the code, he concludes that it falls short of explaining the organization of the code we see today. The recent application of mathematical modeling to study the effects of errors on the course of coevolution, suggests a different conclusion. It shows that coevolution readily generates genetic codes that are highly redundant and similar in their error-correcting organization to the standard code. We review this recent work and suggest that further affirmation of the role of coevolution can be attained by investigating the extent to which the outcome of coevolution is robust to other influences that were present during the evolution of the code.
KeywordsGenetic code Coevolution
We thanks Marcus W. Feldman, Ilan Eshel, Aaron Hirsh, Dmitri Petrov, Michael Lachmann, Tuvik Becker, Ben Kerr, Jennifer Hughes, Steve Freeland, Rob Knight, Erel Levine, Emile Zuckerkandl, and three anonymous reviewers for valuable comments at various stages of this work. We also thank Tsvi Tlusty for his comments and for sharing his exciting results with us. The research of D.A. and G.S. was partly supported by NIH Grants GM28016 and GM28428 to Marcus W. Feldman. G.S. was also supported by a Koshland Scholarship and by the Center for Complexity Science of the Yashaya Horowitz Association.
- Ardell DH (1999) Statistical and dynamical studies in the evolution of the standard genetic code and a biochemical study of variation in resilin from Schistocerca gregaria. PhD thesis. Stanford University, Stanford, CAGoogle Scholar
- de Duve CR (1995) Vital dust. Basic Books, New YorkGoogle Scholar
- Eigen M, Schuster P (1979) The hypercycle: a principle of natural self-organization. Springer, BerlinGoogle Scholar
- El‘skaya AV, Soldatkin AP (1985) The bases of translational fidelity. Molekulyarna Biol 18:1163–1180Google Scholar
- Hixon JE, Brown WM (1986) A comparison of small ribosomal RNA genes from the mitochondrial DNA of great apes and humans: sequence, structure, evolution and phylogenetic implications. Mol Biol Evol 3:1–18Google Scholar
- Nirenberg MW, Jones OW, Leder P, Clark BFC, Sly WS, Pestka S (1963) On the coding of genetic information. Cold Spring Harbor Symp Quant Biol 28:549–558Google Scholar
- Sonneborn TM (1965) Degeneracy of the genetic code: extent, nature, and genetic implications. In: Bryson V, Vogel HJ (eds) Evolving genes and proteins. Academic Press, New York, pp 377–397Google Scholar
- Tlusty T (2006) Emergence of a genetic code as a phase transition induced by error-load topology (Submitted)Google Scholar
- Woese CR (1967) The genetic code: the molecular basis for genetic expression. Harper & Row, New YorkGoogle Scholar
- Zuckerkandl E, Pauling L (1965) Evolutionary divergence and convergence in proteins. In: Bryson V, Vogel HJ (eds) Evolving genes and proteins. Academic Press, New York, pp 97–166Google Scholar