Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2011-1-14
pubmed:abstractText
Ribosomal RNAs are generally stable in growing Escherichia coli cells. However, their degradation increases dramatically under conditions that lead to slow cell growth. In addition, incomplete RNA molecules and molecules with defects in processing, folding, or assembly are also eliminated in growing cells in a process termed quality control. Here, we show that there are significant differences between the pathways of ribosomal RNA degradation during glucose starvation and quality control during steady-state growth. In both processes, endonucleolytic cleavage of rRNA in ribosome subunits is an early step, resulting in accumulation of large rRNA fragments when the processive exoribonucleases, RNase II, RNase R, and PNPase are absent. For 23S rRNA, cleavage is in the region of helix 71, but the exact position can differ in the two degradative processes. For 16S rRNA, degradation during starvation begins with shortening of its 3' end in a reaction catalyzed by RNase PH. In the absence of this RNase, there is no 3' end trimming of 16S rRNA and no accumulation of rRNA fragments, and total RNA degradation is greatly reduced. In contrast, the degradation pattern in quality control remains unchanged when RNase PH is absent. During starvation, the exoribonucleases RNase II and RNase R are important for fragment removal, whereas for quality control, RNase R and PNPase are more important. These data highlight the similarities and differences between rRNA degradation during starvation and quality control during steady-state growth and describe a role for RNase PH in the starvation degradative pathway.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1469-9001
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
338-45
pubmed:dateRevised
2011-6-22
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Degradation of ribosomal RNA during starvation: comparison to quality control during steady-state growth and a role for RNase PH.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural