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| Cobalamin riboswitch |
 |
| Type: |
Cis-reg; riboswitch; |
| 2° structure: |
Predicted; PFOLD |
| Seed alignment: |
Barrick JE, Breaker RR |
| Avg length: |
204.5 nucleotides |
| Avg identity: |
47% |
|
Cobalamin riboswitch also known as B12-element is a cis-regulatory element which is widely distributed in 5' untranslated regions of vitamin B12 (Colbalamin) related genes in bacteria.[1] Riboswitches are metabolite binding domains within certain messenger RNAs (mRNAs) that serve as precision sensors for their corresponding targets. Allosteric rearrangement of mRNA structure is mediated by ligand binding, and this results in modulation of gene expression or translation of mRNA to yield a protein.[2] Cobalamin in the form of adenosylcobalamin (Ado-CBL) is known to repress expression of proteins for vitamin B12 biosynthesis via a post-transcriptional regulatory mechanism that involves direct binding of Ado-CBL to 5' UTRs in relevant genes, preventing ribosome binding and translation of those genes.[1][3]
[edit] References
- ^ a b Nahvi A, Barrick JE, Breaker RR (2004). "Coenzyme B12 riboswitches are widespread genetic control elements in prokaryotes". Nucleic Acids Res. 32 (1): 143–50. doi:10.1093/nar/gkh167. PMID 14704351.
- ^ Mandal M, Boese B, Barrick JE, Winkler WC, Breaker RR (2003). "Riboswitches control fundamental biochemical pathways in Bacillus subtilis and other bacteria". Cell 113 (5): 577–86. PMID 12787499.
- ^ Vitreschak AG, Rodionov DA, Mironov AA, Gelfand MS (2003). "Regulation of the vitamin B12 metabolism and transport in bacteria by a conserved RNA structural element". RNA 9 (9): 1084–97. PMID 12923257.
[edit] External links
