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| PreQ1 riboswitch |
 |
| Type: |
Cis-reg; riboswitch; |
| 2° structure: |
Predicted; Barrick JE |
| Seed alignment: |
Barrick JE |
| Avg length: |
45.9 nucleotides |
| Avg identity: |
61% |
|
The PreQ1-I riboswitch is a cis-acting element identified in bacteria which regulates expression of genes involved in biosynthesis of the nucleoside queuosine from GTP[1]. This RNA element known as a riboswitch binds preQ1 (pre-queuosine1), an intemediate in the queuosine pathway. Riboswitch function has been characterised in the bacterium Bacillus subtilis, where the riboswitch is located in the leader of the ykvJKLM (queCDEF) operon which encodes four genes necessary for queuosine production [2]. In this organism, PreQ1 binding to the riboswitch aptamer is thought to induce premature transcription termination within the leader to down-regulate expression of these genes. The preQ1 riboswitch is distinguished by its unusually small aptamer, compared to other riboswitches. PreQ1-II riboswitches also bind preQ1, but have an unrelated, distinct structure.
[edit] References
- ^ Roth A, Winkler WC, Regulski EE, Lee BW, Lim J, Jona I, Barrick JE, Ritwik A, Kim JN, Welz R, Iwata-Reuyl D, Breaker RR (2007). "A riboswitch selective for the queuosine precursor preQ1 contains an unusually small aptamer domain". Nat Struct Mol Biol 14 (4): 308–17. doi:10.1038/nsmb1224. PMID 17384645.
- ^ Reader JS, Metzgar D, Schimmel P, de Crécy-Lagard V (2004). "Identification of four genes necessary for biosynthesis of the modified nucleoside queuosine". J. Biol. Chem. 279 (8): 6280–5. doi:10.1074/jbc.M310858200. PMID 14660578.
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