- SgrS RNA
SgrS is a 227 nucleotide small RNA that is activated by SgrR in
Escherichia coli duringglucose -phosphate stress. The nature of glucose-phosphate stress is not fully understood, but is correlated with intracellular accumulation ofglucose-6-phosphate . SgrS helps cells recover from glucose-phosphate stress by base pairing with ptsGmRNA (encoding the glucose transporter) and causing its degradation in an RNase E dependent manner. Base pairing between SgrS and ptsGmRNA also requiresHfq , an RNA chaperone frequently required by small RNAs that affect their targets through base pairing. The inability of cells expressing sgrS to create new glucose transporters leads to less glucose uptake and reduced levels ofglucose-6-phosphate . SgrS is an unusual small RNA in that it also encodes a 43amino acid functional polypeptide, SgrT, which helps cells recover from glucose-phosphate stress by preventing glucose uptake. The activity of SgrT does not affect the levels of ptsG mRNA of PtsG protein. It has been proposed that SgrT exerts its effects through regulation of the glucose transporter, PtsG.References
*cite journal | author = Wadler CS, Vanderpool CK | title = A dual function for a bacterial small RNA: SgrS performs base pairing-dependent regulation and encodes a functional polypeptide | journal = PNAS | year = 2007 | pmid = 18042713 | doi = 10.1073/pnas.0708102104 | volume = 104 | pages = 20454
*cite journal | author = Vanderpool CK, Gottesman S | title = The Novel Transcription Factor SgrR Coordinates the Response to Glucose-Phosphate Stress | journal = J. Bact. | volume = 189 | issue = 2 | year = 2007 | pmid = 17209026 | pages = 2238–2248 | doi = 10.1128/JB.01689-06
*cite journal | author = Kawamoto H, Koide Y, Morita T, Aiba H | title = Base-pairing requirement for RNA silencing by a bacterial small RNA and acceleration of duplex formation by Hfq | journal = Mol. Microbiol. | volume = 61 | issue = 4 | pages = 1013–22 | year = 2006 | pmid = 16859494 | doi = 10.1111/j.1365-2958.2006.05288.x | issn =
*cite journal | last = Kawamoto | first = H | coauthors = Morita T, Shimizu A, Inada T, Aiba H | year = 2005 | title = Implication of membrane localization of target mRNA in the action of a small RNA: mechanism of post-transcriptional regulation of glucose transporter in Escherichia coli | journal = Genes Dev | volume = 19 | pages = 328–338 | pmid = 15650111 | doi = 10.1101/gad.1270605
*cite journal | last = Vanderpool | first = CK | coauthors = Gottesman S | year = 2004 | title = Involvement of a novel transcriptional activator and small RNA in post-transcriptional regulation of the glucose phosphoenolpyruvate phosphotransferase system | journal = Mol Microbiol | volume = 54 | pages = 1076–1089 | pmid = 15522088 | doi = 10.1111/j.1365-2958.2004.04348.xReviews
*cite journal | author = Vanderpool CK | title = Physiological consequences of small RNA- mediated regulation of glucose-phosphate stress| journal = Curr. Opin. Micro. | volume = 10| pages = 1–6| year = 2007 | pmid= 17383224
*cite journal | author = Aiba H | title = Mechanism of RNA silencing by Hfq-binding small RNAs | journal = Curr. Opin. Microbiol. | volume = 10 | issue = 2 | pages = 134–9 | year = 2007 | pmid = 17383928 | doi = 10.1016/j.mib.2007.03.010 | issn =
External links
*
* [http://www.mcb.uiuc.edu/faculty/profile/1543 Vanderpool Lab]
* [http://www.bio.nagoya-u.ac.jp/english/seminar/mb1E.html Aiba Lab]
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