Abstract:
:The Escherichia coli Sm-like host factor I (Hfq) is thought to play direct and indirect roles in post-transcriptional regulation by targeting small regulatory RNAs and mRNAs. In this study, we have used proteomics to identify new mRNA targets of Hfq. We have identified 11 candidate proteins, synthesis of which was differentially affected in a hfq- background. The effect of Hfq on some of the corresponding mRNAs including fur, gapA, metF, ppiB and sodB mRNA was assessed, using different in vitro and in vivo methods. This allowed us to distinguish between direct and indirect effects of Hfq in modulating the translational activities of these mRNAs. From the collection of mRNAs tested, only fur and sodB mRNA, encoding the master regulator of iron metabolism and the iron superoxide dismutase, respectively, were found to be regulated by Hfq. Fur is known to be a negative regulator of transcription of the small RNA RyhB. Mutations in the sodB leader and compensating mutations in RyhB revealed that RyhB in turn represses translation of sodB mRNA, explaining the previously reported positive control of sodB by Fur. These data assign a role to Hfq in regulation of iron uptake and in switching off of iron scavenger genes.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Vecerek B,Moll I,Afonyushkin T,Kaberdin V,Bläsi Udoi
10.1046/j.1365-2958.2003.03727.xsubject
Has Abstractpub_date
2003-11-01 00:00:00pages
897-909issue
3eissn
0950-382Xissn
1365-2958pii
3727journal_volume
50pub_type
杂志文章abstract::Maturation of c-type cytochromes in Escherichia coli is a complex process requiring eight membrane proteins encoded by the ccmABCDEFGH operon. CcmE is a mediator of haem delivery. It binds haem transiently at a conserved histidine residue and releases it for directed transfer to apocytochrome c. CcmC, an integral memb...
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pub_type: 杂志文章
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pub_type: 杂志文章
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更新日期:2004-03-01 00:00:00
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pub_type: 杂志文章
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更新日期:2013-08-01 00:00:00
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更新日期:1999-07-01 00:00:00
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pub_type: 杂志文章
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更新日期:1998-01-01 00:00:00
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pub_type: 杂志文章
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更新日期:1995-05-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1995.mmi_18040671.x
更新日期:1995-11-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
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journal_title:Molecular microbiology
pub_type: 杂志文章
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更新日期:1999-09-01 00:00:00
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pub_type: 杂志文章
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journal_title:Molecular microbiology
pub_type: 杂志文章
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更新日期:1990-09-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
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journal_title:Molecular microbiology
pub_type: 杂志文章
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更新日期:1997-04-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
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更新日期:2002-08-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章,评审
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更新日期:1996-09-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12107
更新日期:2013-02-01 00:00:00