RydB RNA

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rydB RNA

RF00118.jpg

Identifiers
Symbol rydB
Rfam RF00118
Other data
RNA type Gene; sRNA
Domain(s) Bacteria
SO 0000655

The RydB RNA is a non-coding RNA originally identified in E. coli in an RNA screen. [1] This gene is only 67 nucleotides in length and is composed of a hairpin like structure. RydB lies between the ydiC and ydiH in E. coli. Homologous RNA genes have been found in other species such as Shigella flexneri and Salmonella species. The molecular function of this RNA is unknown. [1]

Non-coding RNA

A non-coding RNA (ncRNA) is an RNA molecule that is not translated into a protein. The DNA sequence from which a functional non-coding RNA is transcribed is often called an RNA gene. Abundant and functionally important types of non-coding RNAs include transfer RNAs (tRNAs) and ribosomal RNAs (rRNAs), as well as small RNAs such as microRNAs, siRNAs, piRNAs, snoRNAs, snRNAs, exRNAs, scaRNAs and the long ncRNAs such as Xist and HOTAIR.

Nucleotide biological molecules that form the building blocks of nucleic acids

Nucleotides are organic molecules that serve as the monomer units for forming the nucleic acid polymers deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are the building blocks of nucleic acids; they are composed of three subunit molecules: a nitrogenous base, a five-carbon sugar, and at least one phosphate group.

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, base-pair to form a double helix that ends in an unpaired loop. The resulting structure is a key building block of many RNA secondary structures. As an important secondary structure of RNA, it can direct RNA folding, protect structural stability for messenger RNA (mRNA), provide recognition sites for RNA binding proteins, and serve as a substrate for enzymatic reactions.

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GcvB RNA

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SraC/RyeA RNA

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Sib RNA

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RybB RNA

RybB is a small non-coding RNA was identified in a large scale screen of Escherichia coli. The function of this short RNA has been studied using a transcriptomic approach and kinetic analyses of target mRNA decay in vivo. RybB was identified as a factor that selectively accelerates the decay of multiple major omp mRNAs upon induction of the envelope stress response. This RNA has been shown to bind to the Hfq protein.

RyeB RNA

The SdsR/RyeB RNA is a non-coding RNA that was identified in a large scale screen of E. coli. The exact 5' and 3' ends of this RNA are uncertain. This RNA overlaps the SraC/RyeA RNA on the opposite strand suggesting that the two may act in a concerted manner. It is transcribed by general stress factor σs and is most highly expressed in stationary phase. SdsR/RyeB RNA interacts with Hfq.

RyeE RNA

The CyaR RNA non-coding RNA was identified in a large scale screen of Escherichia coli and was called candidate 14. The exact 5' and 3' ends of this RNA are uncertain. This gene lies between yegQ and orgK in E. coli. This small RNA was shown to be bound by the Hfq protein. This RNA has been renamed as CyaR for. It has been shown that the CyaR RNA acts as a repressor of the porin OmpX. It has also been shown that cyaR expression is tightly controlled by the cyclic AMP receptor protein, CRP.

RyfA RNA

The ryfA RNA gene is a non-coding RNA present in E. coli, Shigella flexneri and Salmonella species where it is found between the ydaN and dbpA genes. These RNA genes are about 300 nucleotides in length. The function of this RNA is unknown.

RyhB

RyhB RNA is a 90 nucleotide RNA that down-regulates a set of iron-storage and iron-using proteins when iron is limiting; it is itself negatively regulated by the ferric uptake repressor protein, Fur.

Spot 42 RNA

Spot 42 RNA is a regulatory non-coding bacterial small RNA encoded by the spf gene. Spf is found in gammaproteobacteria and the majority of experimental work on Spot42 has been performed in Escherichia coli and recently in Aliivibrio salmonicida. In the cell Spot42 plays essential roles as a regulator in carbohydrate metabolism and uptake, and its expression is activated by glucose, and inhibited by the cAMP-CRP complex.

T44 RNA

The T44 RNA family consists of a number of bacterial RNA genes of between 135 and 170 bases in length. The t44 gene has been identified in several species of enteric bacteria but homologs have also been identified in Pseudomonas and Coxiella species. The t44 gene is found between the map and rpsB genes in all species in the full alignment apart from Shigella flexneri. The function of this RNA is unknown.

Hok/sok system

The hok/sok system is a postsegregational killing mechanism employed by the R1 plasmid in Escherichia coli. It was the first type I toxin-antitoxin pair to be identified through characterisation of a plasmid-stabilising locus. It is a type I system because the toxin is neutralised by a complementary RNA, rather than a partnered protein.

23S ribosomal RNA A component of the large subunit of the prokaryotic ribosome

The 23S rRNA is a 2904 nt long component of the large subunit (50S) of the bacterial/archean ribosome. The ribosomal peptidyl transferase activity resides in domain V of this rRNA, and this domain is the most common binding site for antibiotics that inhibit translation. A well-known member of this antibiotic class, chloramphenicol, acts by inhibiting peptide bond formation, with recent 3D-structural studies showing two different binding sites depending on the species of ribosome. Linezolid and quinupristin-dalfopristin also bind to the 23S rRNA, and cross-resistance has been demonstrated between these antibiotics. Compared to 16S rRNA genes, 23S rRNA genes typically have higher sequence variations including insertions and/or deletions.

Hfq binding sRNA

An Hfq binding sRNA is an sRNA that binds the bacterial RNA binding protein called Hfq. A number of bacterial small RNAs which have been shown to bind to Hfq have been characterised . Many of these RNAs share a similar structure composed of three stem-loops. Several studies have expanded this list, and experimentally validated a total of 64 Hfq binding sRNA in Salmonella Typhimurium. A transcriptome wide study on Hfq binding sites in Salmonella mapped 126 Hfq binding sites within sRNAs. Genomic SELEX has been used to show that Hfq binding RNAs are enriched in the sequence motif 5'-AAYAAYAA-3'. Genome-wide study identified 40 candidate Hfq-dependent sRNAs in plant pathogen Erwinia amylovora. 12 of them were confirmed by Northern blot.

References

  1. 1 2 Wassarman, KM; Repoila F; Rosenow C; Storz G; Gottesman S (2001). "Identification of novel small RNAs using comparative genomics and microarrays". Genes Dev. 15 (13): 16371651. doi:10.1101/gad.901001. PMC   312727 Lock-green.svg. PMID   11445539.