Linked Life Data

9735284

Source:http://linkedlifedata.com/resource/pubmed/id/9735284

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-10-14
pubmed:abstractText
In Bacilli, ribosomes or 30 S ribosomal subunits that are stalled or bound on mRNAs can stabilize downstream regions, hence the view that the degradation machinery scans mRNAs from their 5' end. In E. coli, several mRNAs can also be stabilized by secondary structures involving their 5' end. To test whether a bound 30 S subunit can act as a 5' stabilizer in E. coli, we compare here the stabilities of two untranslated variants of the lacZ mRNA, the decay of which is controlled by RNase E. In the first variant, a 35 nt region including the Ribosome Binding Site (RBS) is deleted, whereas in the second it is replaced by an 11 nt-long Shine-Dalgarno (SD) sequence lacking an associated start codon. In the latter variant, an 80 nt fragment encompassing the SD and extending up to the mRNA 5' end was stable in vivo (t1/2>one hour), reflecting 30 S binding. Yet, the full-length message was not more stable than when the SD was absent, although two small decay intermediates retaining the 5' end appear somewhat stabilized. A third variant was constructed in which the RBS is replaced by an insert which can fold back onto the lac leader, creating a putative hairpin involving the mRNA 5' end. The fragment corresponding to this hairpin was stable but, again, the full-length message was not stabilized. Thus, the untranslated lacZ mRNA cannot be protected against RNase E by 5' stabilizers, suggesting that mRNA scanning is not an obligate feature of RNase E-controlled degradation. Altogether, these results suggest important differences in mRNA degradation between E. coli and B. subtilis. In addition, we show that mRNA regions involved in stable hairpins or Shine-Dalgarno pairings can be metabolically stable in E. coli.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-2836
pubmed:author
pubmed:copyrightInfo
Copyright 1998 Academic Press.
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
282
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
241-54
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
In the absence of translation, RNase E can bypass 5' mRNA stabilizers in Escherichia coli.
pubmed:affiliation
Laboratoire de Génétique Moléculaire, CNRS URA 1302, Ecole Normale Supérieure, 46 rue d'Ulm, Paris, 75230, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't