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RNA thermometer
An RNA thermometer (or RNA thermosensor) is a temperature-sensitive non-coding RNA molecule which regulates gene expression. Its unique characteristic it is that it does not need proteins or metabolites to function, but only reacts to temperature changes. RNA thermometers often regulate genes required during either a heat shock or cold shock response, but have been implicated in other regulatory roles such as in pathogenicity and starvation.
In general, RNA thermometers operate by changing their secondary structure and tertiary structure in response to temperature fluctuations. This structural transition can then expose or occlude important regions of RNA such as a ribosome binding site, which then affects the translation rate of a nearby protein-coding gene.
RNA thermometers, along with riboswitches, are used as examples in support of the RNA world hypothesis. This theory proposes that RNA was once the sole nucleic acid present in cells, and was replaced by the current DNA → RNA → protein system.
Examples of RNA thermometers include FourU, the Hsp90 cis-regulatory element, the ROSE element, the Lig RNA thermometer, and the Hsp17 thermometer.
The first temperature-sensitive RNA element was reported in 1989. Prior to this research, mutations upstream from the transcription start site in a lambda (λ) phage cIII mRNA were found to affect the level of translation of the cIII protein. This protein is involved in selection of either a lytic or lysogenic life cycle in λ phage, with high concentrations of cIII promoting lysogeny. Further study of this upstream RNA region identified two alternative secondary structures; experimental study found the structures to be interchangeable, and dependent on both magnesium ion concentration and temperature. This RNA thermometer is now thought to encourage entry to a lytic cycle under heat stress in order for the bacteriophage to rapidly replicate and escape the host cell.
The term "RNA thermometer" was not coined until 1999, when it was applied to the rpoH RNA element identified in Escherichia coli. More recently, bioinformatics searches have been employed to uncover several novel candidate RNA thermometers. Traditional sequence-based searches are inefficient, however, as the secondary structure of the element is much more conserved than the nucleic acid sequence.
Biological reactions and organism are sensitive to temperature for cell function. RNA thermometers are an efficient way to respond to temperature because as they allow cells to monitor and sense changes to maintain the cell alive and stable. DNA, RNA, or protein-induced mechanisms avoid small changes because by sensing any external changes
Bacteria use RNA thermometers to enter and survive in their hosts by mounting themselves to their host and causing fluctuations in their temperature. The bacteria can respond quickly against heat-shock and cold-shock conditions since RNA thermometers control gene expression at a translational level.
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RNA thermometer AI simulator
(@RNA thermometer_simulator)
RNA thermometer
An RNA thermometer (or RNA thermosensor) is a temperature-sensitive non-coding RNA molecule which regulates gene expression. Its unique characteristic it is that it does not need proteins or metabolites to function, but only reacts to temperature changes. RNA thermometers often regulate genes required during either a heat shock or cold shock response, but have been implicated in other regulatory roles such as in pathogenicity and starvation.
In general, RNA thermometers operate by changing their secondary structure and tertiary structure in response to temperature fluctuations. This structural transition can then expose or occlude important regions of RNA such as a ribosome binding site, which then affects the translation rate of a nearby protein-coding gene.
RNA thermometers, along with riboswitches, are used as examples in support of the RNA world hypothesis. This theory proposes that RNA was once the sole nucleic acid present in cells, and was replaced by the current DNA → RNA → protein system.
Examples of RNA thermometers include FourU, the Hsp90 cis-regulatory element, the ROSE element, the Lig RNA thermometer, and the Hsp17 thermometer.
The first temperature-sensitive RNA element was reported in 1989. Prior to this research, mutations upstream from the transcription start site in a lambda (λ) phage cIII mRNA were found to affect the level of translation of the cIII protein. This protein is involved in selection of either a lytic or lysogenic life cycle in λ phage, with high concentrations of cIII promoting lysogeny. Further study of this upstream RNA region identified two alternative secondary structures; experimental study found the structures to be interchangeable, and dependent on both magnesium ion concentration and temperature. This RNA thermometer is now thought to encourage entry to a lytic cycle under heat stress in order for the bacteriophage to rapidly replicate and escape the host cell.
The term "RNA thermometer" was not coined until 1999, when it was applied to the rpoH RNA element identified in Escherichia coli. More recently, bioinformatics searches have been employed to uncover several novel candidate RNA thermometers. Traditional sequence-based searches are inefficient, however, as the secondary structure of the element is much more conserved than the nucleic acid sequence.
Biological reactions and organism are sensitive to temperature for cell function. RNA thermometers are an efficient way to respond to temperature because as they allow cells to monitor and sense changes to maintain the cell alive and stable. DNA, RNA, or protein-induced mechanisms avoid small changes because by sensing any external changes
Bacteria use RNA thermometers to enter and survive in their hosts by mounting themselves to their host and causing fluctuations in their temperature. The bacteria can respond quickly against heat-shock and cold-shock conditions since RNA thermometers control gene expression at a translational level.