Attenuation is a regulatory mechanism in gene expression that relies on the premature termination of transcription. It is commonly seen in prokaryotes, particularly in the regulation of amino acid biosynthetic operons.
Operon: A cluster of genes under a single promoter, transcribed together producing polycistronic mRNA.
Leader Sequence: A region upstream of the coding sequence that can form secondary structures influencing transcription termination.
Riboswitch: A regulatory segment of mRNA that binds a small molecule, resulting in changes to gene expression.