Biology:FnrS RNA

From HandWiki
FnrS
FnrS SScons.png
Conserved secondary structure of FnrS RNA. The colour of nucleotides indicate their conservation within the family.
Identifiers
SymbolFnrS
RfamRF01796
Other data
RNA typeGene
Domain(s)Enterobacteriaceae
PDB structuresPDBe

FnrS RNA is a family of Hfq-binding small RNA whose expression is upregulated in response to anaerobic conditions. It is named FnrS because its expression is strongly dependent on fumarate and nitrate reductase regulator (FNR), a direct oxygen availability sensor.[1][2]

A conserved intergenic region between genes ydaN and dbpA was predicted to encode an sRNA, adjacent to where another non-coding RNA (C0343) has been identified.[3] However, northern blot analysis of this 477bp sequence yielded no results.[4] A subsequent tiling array analysis sequencing Hfq-binding sRNA found that the Watson strand did indeed encode an sRNA.[1]

Gene regulation

FnrS has been shown to downregulate 32 different mRNAs in Enterobacteria, in 15 of these cases it does so by base-pairing with the mRNA transcript.[1] The majority of genes downregulated by FnrS are required for aerobic metabolism or the oxidative stress response.[2] Some of the genes downregulated by FnrS are:[1]

A study incorporating comparative target prediction and subsequent experimental verification of selected predictions, suggests that FnrS might be a more global regulator in Escherichia coli. It is predicted to control several transcription factors. These include the verified targets marA and IscR.[9] MarA activates genes involved in the resistance to superoxide,[10] which might not be necessary at the anaerobic conditions where FnrS is expressed. IscR regulates genes for iron-sulfur-cluster containing or biogenesis proteins.[11] FnrS might be involved in the observed O2 dependent expression of the IscR regulon.[11] Further targets of FnrS are nagZ and sdhA.[9]

There is also evidence to suggest that the expression of FnrS is regulated by the RcsCDB signalling system in Salmonella enterica.[12]

References

  1. 1.0 1.1 1.2 1.3 "Reprogramming of anaerobic metabolism by the FnrS small RNA". Mol. Microbiol. 75 (5): 1215–1231. March 2010. doi:10.1111/j.1365-2958.2010.07044.x. PMID 20070527. 
  2. 2.0 2.1 "Translational regulation of gene expression by an anaerobically induced small non-coding RNA in Escherichia coli". J. Biol. Chem. 285 (14): 10690–10702. April 2010. doi:10.1074/jbc.M109.089755. PMID 20075074. PMC 2856277. http://www.jbc.org/cgi/pmidlookup?view=long&pmid=20075074. Retrieved 2010-08-05. 
  3. "Transcriptome analysis of Escherichia coli using high-density oligonucleotide probe arrays". Nucleic Acids Res. 30 (17): 3732–3738. September 2002. doi:10.1093/nar/gkf505. PMID 12202758. 
  4. "A computational approach to identify genes for functional RNAs in genomic sequences". Nucleic Acids Res. 29 (19): 3928–3938. October 2001. doi:10.1093/nar/29.19.3928. PMID 11574674. 
  5. "The cydD gene product, component of a heterodimeric ABC transporter, is required for assembly of periplasmic cytochrome c and of cytochrome bd in Escherichia coli". FEMS Microbiol. Lett. 117 (2): 217–223. April 1994. doi:10.1111/j.1574-6968.1994.tb06768.x. PMID 8181727. 
  6. "Functions of the membrane-associated and cytoplasmic malate dehydrogenases in the citric acid cycle of Escherichia coli". J. Bacteriol. 182 (24): 6892–6899. December 2000. doi:10.1128/jb.182.24.6892-6899.2000. PMID 11092847. 
  7. EntrezGene 944953
  8. EntrezGene 8872708
  9. 9.0 9.1 "Comparative genomics boosts target prediction for bacterial small RNAs.". Proc Natl Acad Sci U S A 110 (37): E3487–E3496. 2013. doi:10.1073/pnas.1303248110. PMID 23980183. Bibcode2013PNAS..110E3487W. 
  10. "Promoter Discrimination at Class I MarA Regulon Promoters Mediated by Glutamic Acid 89 of the MarA Transcriptional Activator of Escherichia coli.". J Bacteriol 193 (2): 506–515. 2011. doi:10.1128/JB.00360-10. PMID 21097628. 
  11. 11.0 11.1 "IscR-dependent gene expression links iron-sulphur cluster assembly to the control of O2-regulated genes in Escherichia coli.". Mol Microbiol 60 (4): 1058–1075. 2006. doi:10.1111/j.1365-2958.2006.05160.x. PMID 16677314. 
  12. "Inverse regulation in the metabolic genes pckA and metE revealed by proteomic analysis of the Salmonella RcsCDB regulon.". J Proteome Res 10 (8): 3386–3398. 2011. doi:10.1021/pr101294v. PMID 21657791. 

Further reading

External links