出典:Wikipedia
出典:『Wikipedia』 (2011/03/25 10:30 UTC 版)
In biology, the PYLIS downstream sequence (PYLIS: pyrrolysine insertion sequence) is a stem-loop structure which appears on some mRNA sequences. This structural motif causes the UAG (amber) stop codon to be translated to the amino acid pyrrolysine instead of ending the protein translation. In archaea the PYLIS downstream sequence is positioned straight after the UAG codon which is translated as pyrrolysine.