operon
Noun A functional unit of DNA in prokaryotic organisms (like bacteria) that contains a cluster of genes under the control of a single promoter. This unit includes structural genes (which code for proteins), an operator (a regulatory DNA sequence), and often associated regulatory genes. The operon allows for the coordinated expression of related genes, typically involved in the same metabolic pathway.
The term is used primarily in genetics and molecular biology to describe a specific model of gene regulation. * The lac operon in E. coli is a classic example of inducible gene expression. * Scientists studied how the operon controls the synthesis of enzymes for tryptophan metabolism. * Regulation of the operon ensures that bacteria produce certain proteins only when needed.
- Inducible operon: An operon that is usually "off" but can be turned "on" (induced) by a specific molecule (e.g., the operon is induced by lactose).
- Repressible operon: An operon that is usually "on" but can be turned "off" (repressed) by a specific molecule (e.g., the operon is repressed by tryptophan).
- Operonic (adjective): Relating to or characteristic of an operon.
- The operonic structure allows for efficient co-transcription.
- Gene cluster (though this is a broader, less specific term)
- Regulatory unit
This is a specialized scientific term with no common alternative meanings outside of genetics.
- a segment of DNA containing adjacent genes including structural genes and an operator gene and a regulatory gene