Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2004-2-23
pubmed:abstractText
The small heat shock proteins (sHSPs) are a ubiquitous class of ATP-independent chaperones believed to prevent irreversible protein aggregation and to facilitate subsequent protein renaturation in cooperation with ATP-dependent chaperones. Although sHSP chaperone activity has been studied extensively in vitro, understanding the mechanism of sHSP function requires identification of proteins that are sHSP substrates in vivo. We have used both immunoprecipitation and affinity chromatography to recover 42 proteins that specifically interact with Synechocystis Hsp16.6 in vivo during heat treatment. These proteins can all be released from Hsp16.6 by the ATP-dependent activity of DnaK and co-chaperones and are heat-labile. Thirteen of the putative substrate proteins were identified by mass spectrometry and reveal the potential for sHSPs to protect cellular functions as diverse as transcription, translation, cell signaling, and secondary metabolism. One of the putative substrates, serine esterase, was purified and tested directly for interaction with purified Hsp16.6. Hsp16.6 effectively formed soluble complexes with serine esterase in a heat-dependent fashion, thereby preventing formation of insoluble serine esterase aggregates. These data offer critical insights into the characteristics of native sHSP substrates and extend and provide in vivo support for the chaperone model of sHSP function.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
27
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7566-75
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:14662763-Adenosine Triphosphate, pubmed-meshheading:14662763-Bacterial Proteins, pubmed-meshheading:14662763-Cell Physiological Phenomena, pubmed-meshheading:14662763-Chromatography, Affinity, pubmed-meshheading:14662763-Cyanobacteria, pubmed-meshheading:14662763-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:14662763-Escherichia coli Proteins, pubmed-meshheading:14662763-Esterases, pubmed-meshheading:14662763-Gene Deletion, pubmed-meshheading:14662763-HSP70 Heat-Shock Proteins, pubmed-meshheading:14662763-Heat-Shock Proteins, pubmed-meshheading:14662763-Hot Temperature, pubmed-meshheading:14662763-Immunosorbent Techniques, pubmed-meshheading:14662763-Mass Spectrometry, pubmed-meshheading:14662763-Molecular Chaperones, pubmed-meshheading:14662763-Mutagenesis, pubmed-meshheading:14662763-Protein Biosynthesis, pubmed-meshheading:14662763-Signal Transduction, pubmed-meshheading:14662763-Transcription, Genetic
pubmed:year
2004
pubmed:articleTitle
The identity of proteins associated with a small heat shock protein during heat stress in vivo indicates that these chaperones protect a wide range of cellular functions.
pubmed:affiliation
Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, Arizona 85721-0106, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.