Global InformationTryptophan operon leader information
| Tryptophan operon leader | |
|---|---|
 Predicted secondary structure and sequence conservation of Trp_leader | |
| Identifiers | |
| Symbol | Trp_leader |
| Rfam | RF00513 |
| Other data | |
| RNA type | Cis-reg; leader |
| Domain(s) | Bacteria |
| SO | SO:0000233 |
| PDB structures | PDBe |
The Tryptophan operon leader is an RNA element found at the 5′ of some bacterial tryptophan operons. The leader sequence can form two different structures known as the terminator and the anti-terminator, based on the Tryptophan amounts in the cell. The leader also codes for very short peptide sequence that is rich in tryptophan. The terminator structure is recognised as a termination signal for RNA polymerase and the operon is not transcribed. This structure forms when the cell has an excess of tryptophan and ribosome movement over the leader transcript is not impeded.[1] When there is a deficiency of the charged tryptophanyl tRNA the ribosome translating the leader peptide stalls and the antiterminator structure can form. This allows RNA polymerase to transcribe the operon.
At least 6 different amino acid operons are known to be regulated by this attenuation.
- ^ Kolter, R; Yanofsky C (1982). "Attenuation in amino acid biosynthetic operons". Annu Rev Genet. 16: 113–134. doi:10.1146/annurev.ge.16.120182.000553. PMID 6186194.