What is Stop codon?
A '''stop codon''', or '''termination codon''', is special sequence in the [[genetic code]]. It is a [[nucleotide]] triplet in [[messenger RNA]] that signals the end of [[translation (genetics)|translation]]. It is a [[codon]] (that is, a [[Sequence analysis|sequence]] of three [[nucleotide]]s in [[messenger RNA]]). It indicates the end of a [[gene]]. Similar to how a [[full stop]] indicates the end of a [[sentence]], a stop codon signals the end of [[Translation (genetics)|genetic translation]].<ref>{{cite book| author=Griffiths A.J.F. | display-authors = etal| title=An introduction to genetic analysis | year=2000| publisher=W.H. Freeman (go to end of excerpt)|chapter-url=https://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=iga.section.1845#1872 |chapter=Chapter 10 (molecular biology of gene function): Genetic code: stop codons}}</ref> They are also called termination codons or chain termination codons. There are three such codons: UAA, UAG and UGA. [[Protein]]s are based on [[polypeptide]]s, which are unique sequences of [[amino acid]]s. Most codons in messenger RNA correspond to the addition of an amino acid to a growing polypeptide chain, which may ultimately become a protein. Stop codons indicate the end of this process, and therefore, the end of [[polypeptide|polypeptide synthesis]]. == References == {{reflist}} {{biology-stub}} [[Category:Molecular biology]]