DsrA RNA
Encyclopedia
DsrA RNA is a non-coding RNA
that regulates both transcription
, by overcoming transcriptional silencing by the nucleoid-associated H-NS protein
, and translation
, by promoting efficient translation of the stress sigma factor, RpoS. These two activities of DsrA can be separated by mutation: the first of three stem-loops
of the 85 nucleotide
RNA
is necessary for RpoS translation but not for anti-H-NS action, while the second stem-loop is essential for antisilencing and less critical for RpoS translation. The third stem-loop, which behaves as a transcription terminator, can be substituted by the trp
transcription terminator without loss of either DsrA function. The sequence of the first stem-loop of DsrA is complementary with the upstream leader portion of RpoS messenger RNA, suggesting that pairing of DsrA with the RpoS message might be important for translational regulation.
There is evidence that DsrA RNA can self-assemble into nanostructures through antisense interactions of three self-complementary regions.
mechanism.
Non-coding RNA
A non-coding RNA is a functional RNA molecule that is not translated into a protein. Less-frequently used synonyms are non-protein-coding RNA , non-messenger RNA and functional RNA . The term small RNA is often used for short bacterial ncRNAs...
that regulates both transcription
Transcription (genetics)
Transcription is the process of creating a complementary RNA copy of a sequence of DNA. Both RNA and DNA are nucleic acids, which use base pairs of nucleotides as a complementary language that can be converted back and forth from DNA to RNA by the action of the correct enzymes...
, by overcoming transcriptional silencing by the nucleoid-associated H-NS protein
Nucleoid
The nucleoid is an irregularly-shaped region within the cell of a prokaryote that contains all or most of the genetic material. In contrast to the nucleus of a eukaryotic cell, it is not surrounded by a nuclear membrane. The genome of prokaryotic organisms generally is a circular, double-stranded...
, and translation
Translation
Translation is the communication of the meaning of a source-language text by means of an equivalent target-language text. Whereas interpreting undoubtedly antedates writing, translation began only after the appearance of written literature; there exist partial translations of the Sumerian Epic of...
, by promoting efficient translation of the stress sigma factor, RpoS. These two activities of DsrA can be separated by mutation: the first of three stem-loops
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,...
of the 85 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...
RNA
RNA
Ribonucleic acid , or RNA, is one of the three major macromolecules that are essential for all known forms of life....
is necessary for RpoS translation but not for anti-H-NS action, while the second stem-loop is essential for antisilencing and less critical for RpoS translation. The third stem-loop, which behaves as a transcription terminator, can be substituted by the trp
Tryptophan
Tryptophan is one of the 20 standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as the codon UGG...
transcription terminator without loss of either DsrA function. The sequence of the first stem-loop of DsrA is complementary with the upstream leader portion of RpoS messenger RNA, suggesting that pairing of DsrA with the RpoS message might be important for translational regulation.
There is evidence that DsrA RNA can self-assemble into nanostructures through antisense interactions of three self-complementary regions.
Targets of DsrA
There is experimental evidence to suggest that DsrA interacts with the protein-coding genes hns,, rbsD, argR, ilvI and rpoS via an anti-senseCis-natural antisense transcript
Natural antisense transcripts are a group of RNAs encoded within a cell that have transcript complementarity to other RNA transcripts. They have been identified in multiple eukaryotes, including humans, mice, yeast and Arabidopsis thaliana. This class of RNAs includes both protein-coding and...
mechanism.