Standish: Changing codon meaning isn’t merely a tweak. As one of the authors notes, “It’s just mind-boggling that an organism could survive that.” But he is dead wrong when he says, “Stop codon shifts are considerably less ‘dramatic’”. Changing a stop codon seems significantly more challenging than changing any other codon meaning because the mechanism for stop codon recognition is totally different and involves more than RNA-RNA interactions.
At The Scientist: “The genetic code has been set in stone for 3 billion years,” study coauthor Yekaterina Shulgina, a Harvard University graduate student in systems biology, tells The Scientist. “The fact that some organisms have found a way to change it is really fascinating to me. Changing the genetic code requires changing ancient, important molecules like tRNAs that are so fundamental to how biology works.”