A normal mitochondrial protein is selectively synthesized and accumulated during heat shock in Tetrahymena thermophila.

McMullin, T W; Hallberg, Richard L.

doi:10.1128/mcb.7.12.4414

Cited by 80 publications

(52 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Like the bacterial GroEL homologue and the Rubisco subunit binding protein, the mitochondrial hsp60 assembles into an oligomeric structure in the cell. The protein of Tetrahymena thermophila sedimented in sucrose gradients as a 20-25S complex (MCMULLIN and HALLBERG 1987). Electron microscopic analysis of the Neurospora crassa protein revealed a structure very similar to that of the GroEL protein.…”

Section: Occurrence and Conserved Propertiesmentioning

confidence: 99%

See 1 more Smart Citation

Heat Shock Proteins hsp60 and hsp70: Their Roles in Folding, Assembly and Membrane Translocation of Proteins

Langer¹,

Neupert²

1991

Current Topics in Microbiology and Immunology

View full text Add to dashboard Cite

Section: Occurrence and Conserved Propertiesmentioning

confidence: 99%

“…The heat-shock protein hsp60 was initially found in mitochondria of Tetrahymena (MCMULLIN and HALLBERG 1987), and then in mitochondria from all organisms analyzed so far. It has a strong structural similarity to the bacterial GroEL.…”

Section: The Mitochondrial Hsp60mentioning

confidence: 99%

Heat Shock Proteins hsp60 and hsp70: Their Roles in Folding, Assembly and Membrane Translocation of Proteins

Langer¹,

Neupert²

1991

Current Topics in Microbiology and Immunology

View full text Add to dashboard Cite

“…After removing nuclei, mitochondria were pelleted at 8100 ϫ g for 10 min at 4°C. Isolated mitochondria from CCL39 -22C5 cells were digested with trypsin as described by McMullin and Hallberg (34). Both the pellet and the released proteins were analyzed by immunoblotting.…”

Section: Methodsmentioning

confidence: 99%

The Small Heat Shock Protein Hsp22 of Drosophila melanogaster Is a Mitochondrial Protein Displaying Oligomeric Organization

Morrow

Inaguma

Kato

et al. 2000

Journal of Biological Chemistry

View full text Add to dashboard Cite

Drosophila melanogaster has four main small heat shock proteins (Hsps), D. melanogaster Hsp22 (DmHsp22), Hsp23 (DmHsp23), Hsp26 (DmHsp26), and Hsp27 (DmHsp27). These proteins, although they have high sequence homology, show distinct developmental expression patterns. The function(s) of each small heat shock protein is unknown. DmHsp22 is shown to localize in mitochondria both in D. melanogaster S2 cells and after heterologous expression in mammalian cells. Fractionation of mitochondria indicates that DmHsp22 resides in the mitochondrial matrix, where it is found in oligomeric complexes, as shown by sedimentation and gel filtration analysis and by cross-linking experiments. Deletion analysis using a DmHsp22-EGFP construct reveals that residues 1-17 and an unknown number of residues between 17-28 are necessary for import. Sitedirected mutagenesis within a putative mitochondrial motif (WRMAEE) at positions 8 -13 shows that the first four residues are necessary for mitochondrial localization. Immunoprecipitation results indicate that there is no interaction between DmHsp22 and the other small heat shock proteins. The mitochondrial localization of this small Hsp22 of Drosophila and its high level of expression in aging suggests a role for this small heat shock protein in protection against oxidative stress.Exposure of organisms to various stresses activates a subset of genes encoding for phylogenically conserved proteins known as the heat shock proteins (Hsps).1 These proteins are commonly divided into families on the basis of molecular weight and sequence homologies. Members of the Hsp70, Hsp90, and Hsp60 families have been shown to act as molecular chaperones in protein folding or refolding following aggregation, and some assist protein translocation through a number of cellular membrane systems. Their chaperone activities are ATP-dependent, and the process is often assisted by co-chaperones. The sHsps comprise a more diverse and less conserved group of proteins, the number and sequences of which vary between and within species. They share a common structural domain in their C termini that shows high homology to the ␣A-and ␣B-crystallins (1). There is evidence for a chaperone-like activity of some sHsps in vitro, where they have been shown to interact with nonnative proteins in an ATP-independent manner (2-5). However, sHsps seem to be rather inefficient chaperones, and they have been suggested to act as reservoirs of nonnative refoldable proteins, which can be refolded in collaboration with other chaperones, such as Hsp70 (6, 7).The role(s) of sHsps in vivo remain unclear. Landry et al. (8) reported that overexpression of human Hsp27 could protect cells from the adverse effects of heat, a phenomenon referred to as thermotolerance. One of the sHsps of Drosophila melanogaster, DmHsp27, also conferred thermal resistance in the same assay (9). This finding is consistent with an early report (10) showing that induction of the Drosophila sHsps by the molting hormone ecdysone was sufficient to confer a thermostable phe...

show abstract

“…Proteins separated by SDS-PAGE were electrophoretically transferred to nitrocellulose membranes (Schleicher & Schuell, Inc.) and probed with antiserum as previously described (34). The second antibody was either a horseradish peroxidase-conjugated goat anti-rabbit immunoglobulin G (IgG) antibody (diluted 1:3,000) or a horseradish peroxidase-conjugated sheep anti-mouse IgG antibody (diluted 1:500).…”

Section: Methodsmentioning

confidence: 99%

“…Heat shock causes the level of hsp58 to increase approximately two-to threefold, and this protein also accumulates specifically in mitochondria. Another interesting property of hsp58 is that it assembles into large oligomeric complexes consisting primarily of the hsp58 protein (34).…”

mentioning

confidence: 99%

A highly evolutionarily conserved mitochondrial protein is structurally related to the protein encoded by the Escherichia coli groEL gene.

McMullin¹,

Hallberg²

1988

Mol. Cell. Biol.

Self Cite

225

122

View full text Add to dashboard Cite

We recently reported that a Tetrahymena thermophila 58-kilodaltodi (kDa) mitochondrial protein (hsp58) was selectively synthesized during heat shock. In this study, we show that hsp58 displayed antigenic similarity with mitochondrially associated proteins from Saccharomyces cerevisiae (64 kDa), Xenopus laevis (60 kDa), Zea mays (62 kDa), and human cells (59 kDa). Furthermore, a 58-kDa protein from Eschenchia coli also exhibited antigenic cross-reactivity to an antiserum directed against the T. thermophila mitochondrial protein. The proteins from S. cerevisiae and E. coli antigenically related to hsp58 were studied in detail and found to share several other characteristics with hsp58, including heat inducibility and the property of associating into distinct oligomeric complexes. The T. thermophila, S. cerevisiae, and E. coli macromolecular complexes containing these related proteins had similar sedimentation characteristics and virtually identical morphologies as seen with the electron microscope. The distinctive properties of the E. coli homolog to T. thermophila hsp58 indicate that it is most likely the product of the groEL gene.Most organisms subjected to sublethal heat shock-inducing temperatures become conditioned to survive at even higher, normally lethal, temperatures. The acquisition of this thermotolerant state is accompanied by the production of specific arrays of polypeptides, collectively known as heat shock proteins (HSPs), which are thought to be involved in protecting the organism from hyperthermic stress (for reviews, see references 8 and 32). Several of these proteins have been shown to exhibit a relatively high degree of evolutionary conservation in their DNA and amino acid sequences (2-5, 12, 24-26, 28), as well as in their subcellular compartmentalization (1,30,45,47). This conservation of structure and localization within the cell strongly suggests that these proteins perform similar functions in the different species in which these proteins are found.In Tetrahymena thermophila, shifting cells to 37 through 41°C induces the selective synthesis of a specific array of HSPs (16,18,19,33,49). Recently, we purified and characterized a minor member of this set of proteins. We find that not only is this protein, hsp58, one of the proteins selectively synthesized and accumulated early in heat shock, but it is also a normal component of the mitochondria of this organism. Heat shock causes the level of hsp58 to increase approximately two-to threefold, and this protein also accumulates specifically in mitochondria. Another interesting property of hsp58 is that it assembles into large oligomeric complexes consisting primarily of the hsp58 protein (34).Since at least two of the HSPs of T. thermophila, hsp73 and hsp80, exhibit evolutionary conservation with HSPs of other species (18), we decided to ask whether homologs of hsp58 also exist in other organisms. This was done by using an antiserum prepared against highly purified hsp58 (34) to probe protein samples from several diverse species. In this study, ...

show abstract

A normal mitochondrial protein is selectively synthesized and accumulated during heat shock in Tetrahymena thermophila.

Cited by 80 publications

References 34 publications

Heat Shock Proteins hsp60 and hsp70: Their Roles in Folding, Assembly and Membrane Translocation of Proteins

Heat Shock Proteins hsp60 and hsp70: Their Roles in Folding, Assembly and Membrane Translocation of Proteins

The Small Heat Shock Protein Hsp22 of Drosophila melanogaster Is a Mitochondrial Protein Displaying Oligomeric Organization

A highly evolutionarily conserved mitochondrial protein is structurally related to the protein encoded by the Escherichia coli groEL gene.

Contact Info

Product

Resources

About