Small heat-shock protein Hsp12 contributes to yeast tolerance to freezing stress

The HSP12 gene encodes one of the two major small heat-shock proteins of Saccharomyces cerevisiae and is induced under different conditions, such as low and high temperatures, osmotic or oxidative stress and high sugar or ethanol concentrations. However, few studies could demonstrate any correlation between HSP12 deletion or overexpression and a phenotype of sensitivity/resistance, making it difficult to attribute a role for Hsp12p under several of these stress conditions. We investigated the possible role of Hsp12p in yeast freezing tolerance. Contrary to what would be expected, the hsp12 null mutant when subjected to prolonged storage at −20 °C showed an increased resistance to freezing when compared with the isogenic wild-type strain. Because the mutant strain displayed a higher intracellular trehalose concentration than the wild-type, which could mask the effect of manipulating HSP12, we overexpressed the HSP12 gene in a trehalose-6-phosphate synthase (TPS1) null mutant. The tps1Δ strain overexpressing HSP12 showed an increase in resistance to freezing storage, indicating that Hsp12p plays a role in freezing tolerance in a way that seems to be interchangeable with trehalose. In addition, we show that overexpression of HSP12 in this tps1Δ strain also increased resistance to heat shock and that absence of HSP12 compromises the ability of yeast cells to accumulate high levels of trehalose in response to a mild heat stress.

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The role of heat-shock proteins in thermotolerance

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1993.0026 ◽

1993 ◽

Vol 339 (1289) ◽

pp. 279-286 ◽

Cited By ~ 123

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

High Temperatures ◽

Fruit Fly ◽

Yeast Cells ◽

Major Protein ◽

Wild Type ◽

Hsp 70 ◽

Shock Proteins

The role of heat-shock proteins (hsps) in thermotolerance was examined in the budding yeast Saccharomyces cerevisiae and in the fruit fly Drosophila melanogaster . In yeast cells, the major protein responsible for thermotolerance is hsp 100. In cells carrying mutations in the hsp 100 gene, HSP 104 , growth is normal at both high and low temperatures, but the ability of cells to survive extreme temperatures is severely impaired. The loss of thermotolerance is apparently due to the absence of the hsp 104 protein itself because, with the exception of the hsp 104 protein, no differences in protein profiles were observed between mutant and wild-type cells. Aggregates found in mutant cells at high temperatures suggest that the cause of death may be the accumulation of denatured proteins. No differences in the rates of protein degradation were observed between mutant and wild-type cells. This, and genetic analysis of cells carrying multiple hsp 70 and hsp 104 mutations, suggests that the primary function of hsp 104 is to rescue proteins from denaturation rather than to degrade them once they have been denatured. Drosophila cells do not produce a protein in the hsp 100 class in response to high temperatures. In this organism, hsp 70 appears to be the primary protein involved in thermotolerance. Thus, the relative importance of different hsps in thermotolerance changes from organism to organism.

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Characterizing the role of Hsp90 in production of heat shock proteins in motor neurons reveals a suppressive effect of wild-type Hsf1

Cell Stress and Chaperones ◽

10.1379/csc-254r.1 ◽

2007 ◽

Vol 12 (2) ◽

pp. 151 ◽

Cited By ~ 18

Author(s):

David M. Taylor ◽

Miranda L. Tradewell ◽

Sandra Minotti ◽

Heather D. Durham

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Motor Neurons ◽

Suppressive Effect ◽

Wild Type ◽

Shock Proteins

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Nucleolar accumulation of poly (A)+ RNA in heat-shocked yeast cells: implication of nucleolar involvement in mRNA transport.

Molecular Biology of the Cell ◽

10.1091/mbc.6.11.1515 ◽

1995 ◽

Vol 6 (11) ◽

pp. 1515-1534 ◽

Cited By ~ 41

Author(s):

T Tani ◽

R J Derby ◽

Y Hiraoka ◽

D L Spector

Keyword(s):

Gene Expression ◽

Heat Shock ◽

Heat Shock Proteins ◽

Schizosaccharomyces Pombe ◽

Yeast Cells ◽

Eukaryotic Cells ◽

Rrna Synthesis ◽

Wild Type ◽

Mrna Transport ◽

Shock Proteins

Transport of mRNA from the nucleus to the cytoplasm plays an important role in gene expression in eukaryotic cells. In wild-type Schizosaccharomyces pombe cells poly(A)+ RNA is uniformly distributed throughout the nucleoplasm and cytoplasm. However, we found that a severe heat shock blocks mRNA transport in S. pombe, resulting in the accumulation of bulk poly(A)+ RNA, as well as a specific intron-less transcript, in the nucleoli. Pretreatment of cells with a mild heat shock, which induces heat shock proteins, before a severe heat shock protects the mRNA transport machinery and allows mRNA transport to proceed unimpeded. In heat-shocked S. pombe cells, the nucleolar region condensed into a few compact structures. Interestingly, poly(A)+ RNA accumulated predominantly in the condensed nucleolar regions of the heat-shocked cells. These data suggest that the yeast nucleolus may play a role in mRNA transport in addition to its roles in rRNA synthesis and preribosome assembly.

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Quaternary Structure and Hetero-Oligomerization of Recombinant Human Small Heat Shock Protein HspB7 (cvHsp)

International Journal of Molecular Sciences ◽

10.3390/ijms22157777 ◽

2021 ◽

Vol 22 (15) ◽

pp. 7777

Author(s):

Lydia K. Muranova ◽

Vladislav M. Shatov ◽

Andrey V. Slushchev ◽

Nikolai B. Gusev

Keyword(s):

Molecular Weight ◽

Heat Shock ◽

Quaternary Structure ◽

Small Heat Shock Protein ◽

Apparent Molecular Weight ◽

Size Exclusion ◽

Wild Type ◽

Simple Method ◽

Exclusion Chromatography ◽

Shock Proteins

In this study, a reliable and simple method of untagged recombinant human HspB7 preparation was developed. Recombinant HspB7 is presented in two oligomeric forms with an apparent molecular weight of 36 kDa (probably dimers) and oligomers with an apparent molecular weight of more than 600 kDa. By using hydrophobic and size-exclusion chromatography, we succeeded in preparation of HspB7 dimers. Mild oxidation promoted the formation of large oligomers, whereas the modification of Cys 126 by iodoacetamide prevented it. The deletion of the first 13 residues or deletion of the polySer motif (residues 17–29) also prevented the formation of large oligomers of HspB7. Cys-mutants of HspB6 and HspB8 containing a single-Cys residue in the central part of the β7 strand in a position homologous to that of Cys137 in HspB1 can be crosslinked to the wild-type HspB7 through a disulfide bond. Immobilized on monoclonal antibodies, the wild-type HspB6 interacted with the wild-type HspB7. We suppose that formation of heterodimers of HspB7 with HspB6 and HspB8 may be important for the functional activity of these small heat shock proteins.

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Nucleolar accumulation of poly (A)+ RNA in heat-shocked yeast cells: implication of nucleolar involvement in mRNA transport.

Molecular Biology of the Cell ◽

10.1091/mbc.7.1.173 ◽

1996 ◽

Vol 7 (1) ◽

pp. 173-192 ◽

Cited By ~ 23

Author(s):

T Tani ◽

R J Derby ◽

Y Hiraoka ◽

D L Spector

Keyword(s):

Gene Expression ◽

Heat Shock ◽

Heat Shock Proteins ◽

Schizosaccharomyces Pombe ◽

Yeast Cells ◽

Eukaryotic Cells ◽

Rrna Synthesis ◽

Wild Type ◽

Mrna Transport ◽

Shock Proteins

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Characterizing the role of Hsp90 in production of heat shock proteins in motor neurons reveals a suppressive effect of wild-type Hsf1

Cell Stress and Chaperones ◽

10.1379/csc-254 ◽

2005 ◽

Vol preprint (2007) ◽

pp. 1

Author(s):

David Taylor ◽

Miranda Tradewell ◽

Sandra Minotti ◽

Heather Durham

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Motor Neurons ◽

Suppressive Effect ◽

Wild Type ◽

Shock Proteins

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HSP Transcript and Protein Accumulation in Brassinosteroid Barley Mutants Acclimated to Low and High Temperatures

International Journal of Molecular Sciences ◽

10.3390/ijms21051889 ◽

2020 ◽

Vol 21 (5) ◽

pp. 1889 ◽

Cited By ~ 5

Author(s):

Iwona Sadura ◽

Marta Libik-Konieczny ◽

Barbara Jurczyk ◽

Damian Gruszka ◽

Anna Janeczko

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Molecular Chaperones ◽

Hormonal Regulation ◽

Protein Accumulation ◽

Main Role ◽

Wild Type ◽

Temperature Dependent ◽

Shock Proteins

In temperature stress, the main role of heat-shock proteins (HSP) is to act as molecular chaperones for other cellular proteins. However, knowledge about the hormonal regulation of the production of the HSP is quite limited. Specifically, little is known about the role of the plant steroid hormones—brassinosteroids (BR)—in regulating the HSP expression. The aim of our study was to answer the question of how a BR deficit or disturbances in its signaling affect the accumulation of the HSP90, HSP70, HSP18, and HSP17 transcripts and protein in barley growing at 20 °C (control) and during the acclimation of plants at 5 °C and 27 °C. In barley, the temperature of plant growth modified the expression of HSPs. Furthermore, the BR-deficient mutants (mutations in the HvDWARF or HvCPD genes) and BR-signaling mutants (mutation in the HvBRI1 gene) were characterized by altered levels of the transcripts and proteins of the HSP group compared to the wild type. The BR-signaling mutant was characterized by a decreased level of the HSP transcripts and heat-shock proteins. In the BR-deficient mutants, there were temperature-dependent cases when the decreased accumulation of the HSP70 and HSP90 transcripts was connected to an increased accumulation of these HSP. The significance of changes in the accumulation of HSPs during acclimation at 27 °C and 5 °C is discussed in the context of the altered tolerance to more extreme temperatures of the studied mutants (i.e., heat stress and frost, respectively).

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CaHSP18.1a, a Small Heat Shock Protein from Pepper (Capsicum Annuum L.), Positively Responds to Heat, Drought, and Salt Tolerance

Horticulturae ◽

10.3390/horticulturae7050117 ◽

2021 ◽

Vol 7 (5) ◽

pp. 117

Author(s):

Yan-Li Liu ◽

Shuai Liu ◽

Jing-Jing Xiao ◽

Guo-Xin Cheng ◽

Haq Saeed ul ◽

...

Keyword(s):

Heat Stress ◽

Heat Shock ◽

Abiotic Stresses ◽

Transgenic Arabidopsis ◽

Small Heat Shock Protein ◽

Wild Type ◽

Drought And Salt Tolerance ◽

Drought And Salt Stresses ◽

Shock Proteins ◽

Resistance To Heat

Pepper is a thermophilic crop, shallow-rooted plant that is often severely affected by abiotic stresses such as heat, salt, and drought. The growth and development of pepper is seriously affected by adverse stresses, resulting in decreases in the yield and quality of pepper crops. Small heat shock proteins (s HSPs) play a crucial role in protecting plant cells against various stresses. A previous study in our laboratory showed that the expression level of CaHSP18.1a was highly induced by heat stress, but the function and mechanism of CaHSP18.1a responding to abiotic stresses is not clear. In this study, we first analyzed the expression of CaHSP18.1a in the thermo-sensitive B6 line and thermo-tolerant R9 line and demonstrated that the transcription of CaHSP18.1a was strongly induced by heat stress, salt, and drought stress in both R9 and B6, and that the response is more intense and earlier in the R9 line. In the R9 line, the silencing of CaHSP18.1a decreased resistance to heat, drought, and salt stresses. The silencing of CaHSP18.1a resulted in significant increases in relative electrolyte leakage (REL) and malonaldehyde (MDA) contents, while total chlorophyll content decreased under heat, salt, and drought stresses. Overexpression analyses of CaHSP18.1a in transgenic Arabidopsis further confirmed that CaHSP18.1a functions positively in resistance to heat, drought, and salt stresses. The transgenic Arabidopsis had higherchlorophyll content and activities of superoxide dismutase, catalase, and ascorbate peroxidase than the wild type (WT). However, the relative conductivity and MDA content were decreased in transgenic Arabidopsis compared to the wild type (WT). We further showed that the CaHSP18.1a protein is localized to the cell membrane. These results indicate CaHSP18.1a may act as a positive regulator of responses to abiotic stresses.

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