Linked Life Data

20158612

Source:http://linkedlifedata.com/resource/pubmed/id/20158612

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2010-5-21
pubmed:abstractText
Small heat-shock proteins (sHSPs) are a widely conserved family of molecular chaperones, all containing a conserved alpha-crystallin domain flanked by variable N- and C-terminal tails. We report that IbpA and IbpB, the sHSPs of Escherichia coli, are substrates for the AAA+ Lon protease. This ATP-fueled enzyme degraded purified IbpA substantially more slowly than purified IbpB, and we demonstrate that this disparity is a consequence of differences in maximal Lon degradation rates and not in substrate affinity. Interestingly, however, IbpB stimulated Lon degradation of IbpA both in vitro and in vivo. Furthermore, although the variable N- and C-terminal tails of the Ibps were dispensable for proteolytic recognition, these tails contain critical determinants that control the maximal rate of Lon degradation. Finally, we show that E. coli Lon degrades variants of human alpha-crystallin, indicating that Lon recognizes conserved determinants in the folded alpha-crystallin domain itself. These results suggest a novel mode for Lon substrate recognition and provide a highly suggestive link between the degradation and sHSP branches of the protein quality-control network.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1365-2958
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
75
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1539-49
pubmed:dateRevised
2011-1-25
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
The IbpA and IbpB small heat-shock proteins are substrates of the AAA+ Lon protease.
pubmed:affiliation
Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural