| Revision as of 22:24, 18 March 2010 editZashaw (talk | contribs)Autopatrolled, Extended confirmed users, Pending changes reviewers1,614 edits ←Created page with 'right|frame|Consensus secondary structure of ''crcB'' RNAs. This figure is adapted from a previous publication.<ref name="Weinberg2010"/> The...' | Revision as of 22:26, 18 March 2010 edit undoZashaw (talk | contribs)Autopatrolled, Extended confirmed users, Pending changes reviewers1,614 editsNo edit summaryNext edit → | ||
| Line 4: | Line 4: | ||
| Many genes are presumed to be regulated by ''crcB'' RNAs. The most common are ''mutS'', which is functions within DNA repair; the ''crcB'' gene that is thought to play a role in ] condensation; transporters of ], ] or ] ]s; the ''nifU'' iron-sulfur protein; and genes that encode ]s. Many ''crcB'' RNAs overlap predicted ] ]s. Assuming that ''crcB'' RNAs are riboswitches whose conserved structure is stabilized by the interaction with their small molecule ligand, high concentrations of this ligand should destabilize the transcription terminators, and thereby lead to increased gene expression. | Many genes are presumed to be regulated by ''crcB'' RNAs. The most common are ''mutS'', which is functions within DNA repair; the ''crcB'' gene that is thought to play a role in ] condensation; transporters of ], ] or ] ]s; the ''nifU'' iron-sulfur protein; and genes that encode ]s. Many ''crcB'' RNAs overlap predicted ] ]s. Assuming that ''crcB'' RNAs are riboswitches whose conserved structure is stabilized by the interaction with their small molecule ligand, high concentrations of this ligand should destabilize the transcription terminators, and thereby lead to increased gene expression. | ||
| Only one other class of riboswitch, the ], is found in organisms other than bacteria. Although several classes of RNAs are present in more than one domain of life (e.g., ] RNAs, ]s, ]s, ] RNAs and ]s), these RNAs are a small minority compared to classes of RNAs restricted to a single domain. Moreover, few of the highly widespread RNAs were initially discovered recently. The biological role played by ''crcB'' RNAs, although currently unknown, is apparently relevant to the physiology of both bacteria and archaea. | Only one other class of riboswitch, the ], is found in organisms other than bacteria. Although several classes of RNAs are present in more than one domain of life (e.g., ] RNAs, ]s, ]s, ] RNAs and ]s), these RNAs are a small minority compared to classes of RNAs restricted to a single domain. Moreover, few of the highly widespread RNAs were initially discovered recently, while ''crcB'' RNAs were first published in 2010. The biological role played by ''crcB'' RNAs, although currently unknown, is apparently relevant to the physiology of both bacteria and archaea. | ||
Revision as of 22:26, 18 March 2010
The crcB RNA motif is a conserved RNA structure identified by bioinformatics in a wide variety of bacteria and archaea. The motif exhibits the rigid or almost perfect conservation of the nucleotide identity at several positions (colored red in the diagram) across two domains of life. Such conservation is consistent with a biochemical requirement to bind a small molecule that does not evolve (like proteins or other RNAs would). Given this observation, and the fact that crcB RNAs are typically located in possible 5' untranslated regions (5' UTRs) of protein-coding genes, it was proposed that crcB RNAs likely function as riboswitches.
Many genes are presumed to be regulated by crcB RNAs. The most common are mutS, which is functions within DNA repair; the crcB gene that is thought to play a role in chromosome condensation; transporters of potassium, sodium or chloride ions; the nifU iron-sulfur protein; and genes that encode formate hydrogen lyases. Many crcB RNAs overlap predicted rho-independent transcription terminator stem-loops. Assuming that crcB RNAs are riboswitches whose conserved structure is stabilized by the interaction with their small molecule ligand, high concentrations of this ligand should destabilize the transcription terminators, and thereby lead to increased gene expression.
Only one other class of riboswitch, the TPP riboswitch, is found in organisms other than bacteria. Although several classes of RNAs are present in more than one domain of life (e.g., ribosomal RNAs, group I introns, group II introns, RNase P RNAs and HDV ribozymes), these RNAs are a small minority compared to classes of RNAs restricted to a single domain. Moreover, few of the highly widespread RNAs were initially discovered recently, while crcB RNAs were first published in 2010. The biological role played by crcB RNAs, although currently unknown, is apparently relevant to the physiology of both bacteria and archaea.
References
- ^ Weinberg Z, Wang JX, Bogue J; et al. (2010). "Comparative genomics reveals 104 candidate structured RNAs from bacteria, archaea and their metagenomes". Genome Biol. 11 (3): R31. doi:10.1186/gb-2010-11-3-r31. PMID 20230605.
{{cite journal}}: Explicit use of et al. in:|author=(help); Unknown parameter|month=ignored (help)CS1 maint: multiple names: authors list (link) CS1 maint: unflagged free DOI (link)
 | This molecular or cell biology article is a stub. You can help Misplaced Pages by expanding it. |