Why has nature invented three stop codons of DNA and only one start codon?

0376822 - MÚ 2013 RIV GB eng J - Journal Article
Křížek, Michal - Křížek, P.
Why has nature invented three stop codons of DNA and only one start codon?
Journal of Theoretical Biology. Roč. 304, Jul 7 (2012), s. 183-187. ISSN 0022-5193. E-ISSN 1095-8541
R&D Projects: GA AV ČR(CZ) IAA100190803
Institutional support: RVO:67985840
Keywords : DNA * RNA * stop codon * synchronization shift * drosophila genome
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 2.351, year: 2012
http://www.sciencedirect.com/science/article/pii/S0022519312001580

We examine the standard genetic code with three stop codons. Assuming that the synchronization period of length 3 in DNA or RNA is violated during the transcription or translation processes, the probability of reading a frameshifted stop codon is higher than if the code would have only one stop codon. Consequently, the synthesis of RNA or proteins will soon terminate. In this way, cells do not produce undesirable proteins and essentially save energy. This hypothesis is tested on the AT-rich Drosophila genome, where the detection of frameshifted stop codons is even higher than the theoretical value. Using the binomial theorem, we establish the probability of reading a frameshifted stop codon within n steps. Since the genetic code is largely redundant, there is still space for some hidden secondary functions of this code.
Permanent Link: http://hdl.handle.net/11104/0209131