Repression of heat shock gene expression (ROSE) element
Encyclopedia
The repression of heat shock gene expression (ROSE) element is an RNA element
Cis-regulatory element
A cis-regulatory element or cis-element is a region of DNA or RNA that regulates the expression of genes located on that same molecule of DNA . This term is constructed from the Latin word cis, which means "on the same side as". These cis-regulatory elements are often binding sites for one or...

 found in the 5' UTR of some heat shock protein's mRNAs. The ROSE element is an RNA thermometer
RNA thermometer
An RNA thermometer is a temperature-sensitive non-coding RNA molecule which regulates gene expression. 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...

 that negatively regulates heat shock
Heat shock
In biochemistry, heat shock is the effect of subjecting a cell to a higher temperature than that of the ideal body temperature of the organism from which the cell line was derived.-Heat shock response:...

 gene expression
Gene expression
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. These products are often proteins, but in non-protein coding genes such as ribosomal RNA , transfer RNA or small nuclear RNA genes, the product is a functional RNA...

. The secondary structure is thought to be altered by temperature, thus it is an RNA thermometer. This structure blocks access to the ribosome binding site
Shine-Dalgarno sequence
The Shine-Dalgarno sequence , proposed by Australian scientists John Shine and Lynn Dalgarno , is a ribosomal binding site in the mRNA, generally located 8 basepairs upstream of the start codon AUG. The Shine-Dalgarno sequence exists only in prokaryotes. The six-base consensus sequence is AGGAGG;...

 at normal temperatures. During heat shock however, the structure changes freeing the ribosome
Ribosome
A ribosome is a component of cells that assembles the twenty specific amino acid molecules to form the particular protein molecule determined by the nucleotide sequence of an RNA molecule....

 binding site and allowing expression to occur.

A partial structure of this RNA element has been determined using NMR
NMR
NMR may refer to:Applications of Nuclear Magnetic Resonance:* Nuclear magnetic resonance* NMR spectroscopy* Solid-state nuclear magnetic resonance* Protein nuclear magnetic resonance spectroscopy* Proton NMR* Carbon-13 NMR...

.

ROSE1 and ROSEAT2

ROSE1 and ROSEAT2 are specific examples of ROSE elements. ROSE1 is found in Bradyrhizobium japonicum
Bradyrhizobium japonicum
Bradyrhizobium japonicum is a species of legume-root nodulating, microsymbiotic nitrogen-fixing bacterium species. B. japonicum is identified as a DNA homology group .B...

whereas ROSEAT2 is a closely related element from Agrobacterium tumefaciens
Agrobacterium tumefaciens
Agrobacterium tumefaciens is the causal agent of crown gall disease in over 140 species of dicot. It is a rod shaped, Gram negative soil bacterium...

. The two RNA elements have similar secondary structure
Secondary structure
In biochemistry and structural biology, secondary structure is the general three-dimensional form of local segments of biopolymers such as proteins and nucleic acids...

s with ROSE1 having an extra hairpin
Stem-loop
Stem-loop intramolecular base pairing is a pattern that can occur in single-stranded DNA or, more commonly, in RNA. The structure is also known as a hairpin or hairpin loop. It occurs when two regions of the same strand, usually complementary in nucleotide sequence when read in opposite directions,...

. All ROSE elements contain a characteristic 'bulged G' opposite the Shine-Dalgarno sequence
Shine-Dalgarno sequence
The Shine-Dalgarno sequence , proposed by Australian scientists John Shine and Lynn Dalgarno , is a ribosomal binding site in the mRNA, generally located 8 basepairs upstream of the start codon AUG. The Shine-Dalgarno sequence exists only in prokaryotes. The six-base consensus sequence is AGGAGG;...

 binding site, without this nucleotide
Nucleotide
Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA. In addition, nucleotides participate in cellular signaling , and are incorporated into important cofactors of enzymatic reactions...

the RNA thermometer loses its temperature-sensitivity.
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