Enhancement of Neutral Trehalase Activity by Oxidative Stress in the Fission YeastSchizosaccharomyces pombe

A variety of results has been obtained consistent with activation of neutral trehalase in Saccharomyces cerevisiae through direct phosphorylation by cAMP-dependent protein kinase (PKA). A series of neutral trehalase mutant alleles, in which all evolutionarily conserved putative phosphorylation sites were changed into alanine, was tested for activation in vitro (by PKA) and in vivo (by glucose addition). None of the mutations alone affected the activation ratio, whereas all mutations combined resulted in an inactive enzyme. All mutant alleles were expressed to similar levels, as shown by Western blotting. Several of the point mutations significantly lowered the specific activity. Using this series of mutants with different activity levels we show an inverse relationship between trehalase activity and heat-shock survival during glucose-induced trehalose mobilization. This is consistent with a stress-protective function of trehalose. On the other hand, reduction of trehalase activity below a certain threshold level impaired recovery from a sublethal heat shock. This suggests that trehalose breakdown is required for efficient recovery from heat shock, and that the presence of trehalase protein alone is not sufficient for efficient heat-stress recovery.

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A method to study the rapid phosphorylation-related modulation of neutral trehalase activity by temperature shifts in yeast

FEBS Letters ◽

10.1016/0014-5793(91)81319-4 ◽

1991 ◽

Vol 291 (2) ◽

pp. 355-358 ◽

Cited By ~ 29

Author(s):

Claudio De Virgilio ◽

Niels Bürckert ◽

Thomas Boller ◽

Andres Wiemken

Keyword(s):

Trehalase Activity ◽

Neutral Trehalase

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A role for calcium in the regulation of neutral trehalase activity in the fission yeast Schizosaccharomyces pombe

Biochemical Journal ◽

10.1042/bj20030825 ◽

2003 ◽

Vol 376 (1) ◽

pp. 209-217 ◽

Cited By ~ 19

Author(s):

Alejandro FRANCO ◽

Teresa SOTO ◽

Jero VICENTE-SOLER ◽

Vanessa PAREDES ◽

Marisa MADRID ◽

...

Keyword(s):

Schizosaccharomyces Pombe ◽

Fission Yeast ◽

Active Form ◽

Gel Filtration ◽

General Mechanism ◽

Binding Motif ◽

Trehalase Activity ◽

Cell Extracts ◽

Neutral Trehalase

Neutral trehalases mobilize trehalose accumulated by fungal cells as a protective and storage carbohydrate. A structural feature of these enzymes is the presence of an EF-like motif similar to that shown by many Ca2+-binding proteins. In this study we provide direct evidence for physical binding of Ca2+ to neutral trehalase (Ntp1p) of the fission yeast Schizosaccharomyces pombe, and show that aspartic residues at positions 97 and 108 in the conserved putative Ca2+-binding motif of Ntp1p appear to be responsible for this interaction. Mutations in these residues do not interfere with the ability of Ntp1p to associate in vivo with trehalose-6-phosphate synthase, but prevent activation of neutral trehalase triggered by the addition of glucose or by subjecting cells to stressing conditions. Strains expressing Ntp1p variants that are unable to bind Ca2+ partially resemble those devoid of the ntp1+ gene in terms of trehalose hyperaccumulation. Gel filtration of cell extracts from wild-type cells after EDTA treatment or from cells containing Ntp1p with mutations in aspartic acid residues within the Ca2+-binding site revealed that Ntp1p eluted mainly in an inactive conformation instead of the dimeric or trimeric active form of the enzyme. These results suggest that activation of S. pombe Ntp1p under different conditions depends upon Ca2+ binding through the Ca2+-binding motif as a prerequisite for correct enzyme oligomerization to its active form. Given the high degree of conservation of the Ca2+ accommodation site, this might be a general mechanism regulating neutral trehalase activity in other yeasts and filamentous fungi.

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Osmo-stress-induced changes in neutral trehalase activity of the fission yeast Schizosaccharomyces pombe

Biochimica et Biophysica Acta (BBA) - Molecular Cell Research ◽

10.1016/s0167-4889(97)00010-4 ◽

1997 ◽

Vol 1357 (1) ◽

pp. 41-48 ◽

Cited By ~ 13

Author(s):

J Fernández ◽

T Soto ◽

J Vicente-Soler ◽

J Cansado ◽

M Gacto

Keyword(s):

Schizosaccharomyces Pombe ◽

Fission Yeast ◽

Trehalase Activity ◽

Neutral Trehalase ◽

Induced Changes

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Characterization of Mutants Devoid of Neutral Trehalase Activity in the Fission Yeast Schizosaccharomyces pombe: Partial Protection from Heat Shock and High-Salt Stress

Journal of Bacteriology ◽

10.1128/jb.180.5.1342-1345.1998 ◽

1998 ◽

Vol 180 (5) ◽

pp. 1342-1345 ◽

Cited By ~ 17

Author(s):

Jose Cansado ◽

Teresa Soto ◽

Juana Fernandez ◽

Jero Vicente-Soler ◽

Mariano Gacto

Keyword(s):

Heat Shock ◽

Schizosaccharomyces Pombe ◽

Transcriptional Activation ◽

Gene Replacement ◽

Media Analysis ◽

Trehalase Activity ◽

Neutral Trehalase ◽

Solid Media ◽

Hydrolysis Of

ABSTRACT Exposure of cells of Schizosaccharomyces pombe to heat shock or osmotic upshift results in an increased level of neutral trehalase activity, which is responsible for hydrolysis of intracellular trehalose. We constructed S. pombe mutants lacking neutral trehalase activity by gene replacement at the newly defined ntp1 + locus. Analysis of these mutants revealed that a twofold increase in trehalose accumulation, enhanced acquired thermoresistance, and marked salt tolerance characterized their ability to grow in liquid and solid media. Analysis of the expression of the trehalase gene under heat shock and osmotic upshift revealed the transcriptional activation ofntp1 + in response to both stresses.

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Lycopene alleviates sulfamethoxazole-induced hepatotoxicity in grass carp (Ctenopharyngodon idellus) via suppression of oxidative stress, inflammation and apoptosis

Food & Function ◽

10.1039/d0fo01638a ◽

2020 ◽

Vol 11 (10) ◽

pp. 8547-8559

Author(s):

Hongjing Zhao ◽

Yu Wang ◽

Mengyao Mu ◽

Menghao Guo ◽

Hongxian Yu ◽

...

Keyword(s):

Oxidative Stress ◽

Secondary Metabolites ◽

Human Health ◽

Grass Carp ◽

Aquatic Environment ◽

Ctenopharyngodon Idellus

Antibiotics are used worldwide to treat diseases in humans and other animals; most of them and their secondary metabolites are discharged into the aquatic environment, posing a serious threat to human health.

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Copper-dependent ATP7B up-regulation drives the resistance of TMEM16A-overexpressing head-and-neck cancer models to platinum toxicity

Biochemical Journal ◽

10.1042/bcj20190591 ◽

2019 ◽

Vol 476 (24) ◽

pp. 3705-3719 ◽

Cited By ~ 2

Author(s):

Avani Vyas ◽

Umamaheswar Duvvuri ◽

Kirill Kiselyov

Keyword(s):

Oxidative Stress ◽

Head And Neck ◽

Transcriptional Activation ◽

Platinum Resistance ◽

Mrna Levels ◽

Strong Positive Correlation ◽

Platinum Compounds ◽

Copper Chelation ◽

Novel Approach ◽

Cancer Models

Platinum-containing drugs such as cisplatin and carboplatin are routinely used for the treatment of many solid tumors including squamous cell carcinoma of the head and neck (SCCHN). However, SCCHN resistance to platinum compounds is well documented. The resistance to platinum has been linked to the activity of divalent transporter ATP7B, which pumps platinum from the cytoplasm into lysosomes, decreasing its concentration in the cytoplasm. Several cancer models show increased expression of ATP7B; however, the reason for such an increase is not known. Here we show a strong positive correlation between mRNA levels of TMEM16A and ATP7B in human SCCHN tumors. TMEM16A overexpression and depletion in SCCHN cell lines caused parallel changes in the ATP7B mRNA levels. The ATP7B increase in TMEM16A-overexpressing cells was reversed by suppression of NADPH oxidase 2 (NOX2), by the antioxidant N-Acetyl-Cysteine (NAC) and by copper chelation using cuprizone and bathocuproine sulphonate (BCS). Pretreatment with either chelator significantly increased cisplatin's sensitivity, particularly in the context of TMEM16A overexpression. We propose that increased oxidative stress in TMEM16A-overexpressing cells liberates the chelated copper in the cytoplasm, leading to the transcriptional activation of ATP7B expression. This, in turn, decreases the efficacy of platinum compounds by promoting their vesicular sequestration. We think that such a new explanation of the mechanism of SCCHN tumors’ platinum resistance identifies novel approach to treating these tumors.

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