Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
Small heat shock proteins protect cells from stress presumably by acting as molecular chaperones. Here we report on the functional characterization of a developmentally regulated, heat-inducible member of the Xenopus small heat shock protein family, Hsp30C. An expression vector containing the open reading frame of the Hsp30C gene was expressed in Escherichia coli. These bacterial cells displayed greater thermoresistance than wild type or plasmid-containing cells. Purified recombinant protein, 30C, was recovered as multimeric complexes which inhibited heat-induced aggregation of either citrate synthase or luciferase as determined by light scattering assays. Additionally, 30C attenuated but did not reverse heat-induced inactivation of enzyme activity. In contrast to an N-terminal deletion mutant, removal of the last 25 amino acids from the C-terminal end of 30C severely impaired its chaperone activity. Furthermore, heat-treated concentrated solutions of the C-terminal mutant formed nonfunctional complexes and precipitated from solution. Immunoblot and gel filtration analysis indicated that 30C binds with and maintains the solubility of luciferase preventing it from forming heat-induced aggregates. Coimmunoprecipitation experiments suggested that the carboxyl region is necessary for 30C to interact with target proteins. These results clearly indicate a molecular chaperone role for Xenopus Hsp30C and provide evidence that its activity requires the carboxyl terminal region.
Andley,
Cloning, expression, and chaperone-like activity of human alphaA-crystallin.
1996, Pubmed
Andley,
Cloning, expression, and chaperone-like activity of human alphaA-crystallin.
1996,
Pubmed
Arrigo,
Small stress proteins: chaperones that act as regulators of intracellular redox state and programmed cell death.
1998,
Pubmed
Behlke,
Supramolecular structure of the recombinant murine small heat shock protein hsp25.
1991,
Pubmed
Beissinger,
How chaperones fold proteins.
1998,
Pubmed
Buchner,
Analysis of chaperone function using citrate synthase as nonnative substrate protein.
1998,
Pubmed
Carver,
On the interaction of alpha-crystallin with unfolded proteins.
1995,
Pubmed
Carver,
Identification by 1H NMR spectroscopy of flexible C-terminal extensions in bovine lens alpha-crystallin.
1992,
Pubmed
Chang,
Mycobacterium tuberculosis 16-kDa antigen (Hsp16.3) functions as an oligomeric structure in vitro to suppress thermal aggregation.
1996,
Pubmed
de Jong,
Dogfish alpha-crystallin sequences. Comparison with small heat shock proteins and Schistosoma egg antigen.
1988,
Pubmed
,
Xenbase
Ehrnsperger,
Binding of non-native protein to Hsp25 during heat shock creates a reservoir of folding intermediates for reactivation.
1997,
Pubmed
Gu,
Recombinant proteins attached to a nickel-NTA column: use in affinity purification of antibodies.
1994,
Pubmed
Haley,
The small heat-shock protein, alphaB-crystallin, has a variable quaternary structure.
1998,
Pubmed
Hartl,
Molecular chaperones in cellular protein folding.
1996,
Pubmed
Heikkila,
Heat shock protein gene expression during Xenopus development.
1997,
Pubmed
,
Xenbase
Huot,
HSP27 phosphorylation-mediated resistance against actin fragmentation and cell death induced by oxidative stress.
1996,
Pubmed
Jakob,
Assisting spontaneity: the role of Hsp90 and small Hsps as molecular chaperones.
1994,
Pubmed
Kroll,
A multifunctional prokaryotic protein expression system: overproduction, affinity purification, and selective detection.
1993,
Pubmed
Krone,
Expression of microinjected hsp 70/CAT and hsp 30/CAT chimeric genes in developing Xenopus laevis embryos.
1989,
Pubmed
,
Xenbase
Krone,
Comparison of regulatory and structural regions of the Xenopus laevis small heat-shock protein-encoding gene family.
1992,
Pubmed
,
Xenbase
Krone,
Analysis of hsp 30, hsp 70 and ubiquitin gene expression in Xenopus laevis tadpoles.
1988,
Pubmed
,
Xenbase
Lang,
Spatial pattern of constitutive and heat shock-induced expression of the small heat shock protein gene family, Hsp30, in Xenopus laevis tailbud embryos.
1999,
Pubmed
,
Xenbase
Lee,
Structure and in vitro molecular chaperone activity of cytosolic small heat shock proteins from pea.
1995,
Pubmed
Lee,
A small heat shock protein stably binds heat-denatured model substrates and can maintain a substrate in a folding-competent state.
1997,
Pubmed
Leroux,
Structure-function studies on small heat shock protein oligomeric assembly and interaction with unfolded polypeptides.
1997,
Pubmed
Liang,
Purification, structure and in vitro molecular-chaperone activity of Artemia p26, a small heat-shock/alpha-crystallin protein.
1997,
Pubmed
Liang,
The synthesis of a small heat shock/alpha-crystallin protein in Artemia and its relationship to stress tolerance during development.
1999,
Pubmed
Marin,
hsp23 and hsp26 exhibit distinct spatial and temporal patterns of constitutive expression in Drosophila adults.
1993,
Pubmed
Mehlen,
hsp27 as a switch between differentiation and apoptosis in murine embryonic stem cells.
1997,
Pubmed
Mehlen,
Small stress protein Hsp27 accumulation during dopamine-mediated differentiation of rat olfactory neurons counteracts apoptosis.
1999,
Pubmed
Mehlen,
Analysis of the resistance to heat and hydrogen peroxide stresses in COS cells transiently expressing wild type or deletion mutants of the Drosophila 27-kDa heat-shock protein.
1993,
Pubmed
Merck,
Structural and functional similarities of bovine alpha-crystallin and mouse small heat-shock protein. A family of chaperones.
1993,
Pubmed
Mirkes,
Induction of heat shock protein 27 in rat embryos exposed to hyperthermia.
1996,
Pubmed
Muchowski,
Human alphaB-crystallin. Small heat shock protein and molecular chaperone.
1997,
Pubmed
Muchowski,
ATP-enhanced molecular chaperone functions of the small heat shock protein human alphaB crystallin.
1998,
Pubmed
Ohan,
Involvement of differential gene expression and mRNA stability in the developmental regulation of the hsp 30 gene family in heat-shocked Xenopus laevis embryos.
1995,
Pubmed
,
Xenbase
Ohan,
Characterization of a novel group of basic small heat shock proteins in Xenopus laevis A6 kidney epithelial cells.
1998,
Pubmed
,
Xenbase
Ohan,
Heat-shock-induced assembly of Hsp30 family members into high molecular weight aggregates in Xenopus laevis cultured cells.
1998,
Pubmed
,
Xenbase
Smulders RHPH,
Immobilization of the C-terminal extension of bovine alphaA-crystallin reduces chaperone-like activity.
1996,
Pubmed
Stringham,
Temporal and spatial expression patterns of the small heat shock (hsp16) genes in transgenic Caenorhabditis elegans.
1992,
Pubmed
Studier,
Use of T7 RNA polymerase to direct expression of cloned genes.
1990,
Pubmed
Takemoto,
The C-terminal region of alpha-crystallin: involvement in protection against heat-induced denaturation.
1993,
Pubmed
Tam,
Identification of members of the HSP30 small heat shock protein family and characterization of their developmental regulation in heat-shocked Xenopus laevis embryos.
1995,
Pubmed
,
Xenbase
Tanguay,
Tissue-specific expression of heat shock proteins of the mouse in the absence of stress.
1993,
Pubmed
Wistow,
Domain structure and evolution in alpha-crystallins and small heat-shock proteins.
1985,
Pubmed
Yahara,
Stress-inducible cellular responses. Introduction.
1996,
Pubmed