Yanofsky C
Nature. 1981 Feb 26;289(5800):751-8. doi: 10.1038/289751a0.
Bacterial operons concerned with the biosynthesis of amino acids are often controlled by a process of attenuation. The translation product of the initial segment of the transcript of each operon is a peptide rich in the amino acid that the particular operon controls. If the amino acid is in short supply translation is stalled at the relevant codons of the transcript long enough for the succeeding segment of the transcript to form secondary structures that allow the transcribing RNA polymerase molecule to proceed through a site that otherwise dictates termination of transcription. This site is the attenuator; the process is attenuation.
与氨基酸生物合成相关的细菌操纵子通常受衰减过程的控制。每个操纵子转录本初始片段的翻译产物是一种富含该特定操纵子所控制氨基酸的肽。如果氨基酸供应不足，翻译会在转录本的相关密码子处停滞足够长的时间，以便转录本的后续片段形成二级结构，从而使正在转录的RNA聚合酶分子能够通过一个否则会导致转录终止的位点。这个位点就是衰减子；这个过程就是衰减作用。
