The gene cutA of Fusarium fujikuroi, encoding a protein of the haloacid dehalogenase family, is involved in osmotic stress and glycerol metabolism

Survival of micro-organisms in natural habitats depends on their ability to adapt to variations in osmotic conditions. We previously described the gene cut-1 of Neurospora crassa, encoding a protein of the haloacid dehalogenase family with an unknown function in the osmotic stress response. Here we report on the functional analysis of cutA, the orthologous gene in the phytopathogenic fungus Fusarium fujikuroi. cutA mRNA levels increased transiently after exposure to 0.68 M NaCl and were reduced upon return to normal osmotic conditions; deletion of the gene resulted in a partial reduction in tolerance to osmotic stress. ΔcutA mutants contained much lower intracellular levels of glycerol than the wild-type, and did not exhibit the increase following hyper-osmotic shock expected from the high osmolarity glycerol (HOG) response. cutA is linked and divergently transcribed with the putative glycerol dehydrogenase gene gldB, which showed the same regulation by osmotic shock. The intergenic cutA/gldB regulatory region contains putative stress-response elements conserved in other fungi, and both genes shared other regulatory features, such as induction by heat shock and by illumination. Photoinduction was also observed in the HOG response gene hogA, and was lost in mutants of the white collar gene wcoA. Previous data on glycerol production in Aspergillus spp. and features of the predicted CutA protein lead us to propose that F. fujikuroi produces glycerol from dihydroxyacetone, and that CutA is the enzyme involved in the synthesis of this precursor by dephosphorylation of dihydroxyacetone-3P.

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Expression of YAP4 in Saccharomyces cerevisiae under osmotic stress

Biochemical Journal ◽

10.1042/bj20031127 ◽

2004 ◽

Vol 379 (2) ◽

pp. 367-374 ◽

Cited By ~ 24

Author(s):

Tracy NEVITT ◽

Jorge PEREIRA ◽

Dulce AZEVEDO ◽

Paulo GUERREIRO ◽

Claudina RODRIGUES-POUSADA

Keyword(s):

Saccharomyces Cerevisiae ◽

Stress Response ◽

Osmotic Stress ◽

Osmotic Shock ◽

Glycerol Dehydrogenase ◽

Mrna Levels ◽

Yeast Saccharomyces Cerevisiae ◽

Moderate Growth ◽

Mutant Induction ◽

Decapping Enzyme

YAP4, a member of the yeast activator protein (YAP) gene family, is induced in response to osmotic shock in the yeast Saccharomyces cerevisiae. The null mutant displays mild and moderate growth sensitivity at 0.4 M and 0.8 M NaCl respectively, a fact that led us to analyse YAP4 mRNA levels in the hog1 (high osmolarity glycerol) mutant. The data obtained show a complete abolition of YAP4 gene expression in this mutant, placing YAP4 under the HOG response pathway. YAP4 overexpression not only suppresses the osmosensitivity phenotype of the yap4 mutant but also relieves that of the hog1 mutant. Induction, under the conditions tested so far, requires the presence of the transcription factor Msn2p, but not of Msn4p, as YAP4 mRNA levels are depleted by at least 75% in the msn2 mutant. This result was further substantiated by the fact that full YAP4 induction requires the two more proximal stress response elements. Furthermore we find that GCY1, encoding a putative glycerol dehydrogenase, GPP2, encoding a NAD-dependent glycerol-3-phosphate phosphatase, and DCS2, a homologue to a decapping enzyme, have decreased mRNA levels in the yap4-deleted strain. Our data point to a possible, as yet not entirely understood, role of the YAP4 in osmotic stress response.

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Light-Dependent Functions of the Fusarium fujikuroi CryD DASH Cryptochrome in Development and Secondary Metabolism

Applied and Environmental Microbiology ◽

10.1128/aem.03110-12 ◽

2013 ◽

Vol 79 (8) ◽

pp. 2777-2788 ◽

Cited By ~ 41

Author(s):

Marta Castrillo ◽

Jorge García-Martínez ◽

Javier Avalos

Keyword(s):

Secondary Metabolism ◽

Nitrogen Starvation ◽

Phytopathogenic Fungus ◽

Fusarium Fujikuroi ◽

Mrna Levels ◽

Wild Type ◽

Gene Encoding ◽

Content Type ◽

Gibberellin Production ◽

In The Wild

ABSTRACTDASH (Drosophila,Arabidopsis,Synechocystis, human) cryptochromes (cry-DASHs) constitute a subgroup of the photolyase cryptochrome family with diverse light-sensing roles, found in most taxonomical groups. The genome ofFusarium fujikuroi, a phytopathogenic fungus with a rich secondary metabolism, contains a gene encoding a putative cry-DASH, named CryD. The expression of thecryDgene is induced by light in the wild type, but not in mutants of the “white collar” genewcoA. Targeted ΔcryDmutants show light-dependent phenotypic alterations, including changes in morphology and pigmentation, which disappear upon reintroduction of a wild-typecryDallele. In addition to microconidia, the colonies of the ΔcryDmutants produced under illumination and nitrogen starvation large septated spores called macroconidia, absent in wild-type colonies. The ΔcryDmutants accumulated similar amounts of carotenoids to the control strain under constant illumination, but produced much larger amounts of bikaverin under nitrogen starvation, indicating a repressing role for CryD in this biosynthetic pathway. Additionally, a moderate photoinduction of gibberellin production was exhibited by the wild type but not by the ΔcryDmutants. The phenotypic alterations of the ΔcryDmutants were only noticeable in the light, as expected from the low expression ofcryDin the dark, but did not correlate with mRNA levels for structural genes of the bikaverin or gibberellin biosynthetic pathways, suggesting the participation of CryD in posttranscriptional regulatory mechanisms. This is the first report on the participation of a cry-DASH protein in the regulation of fungal secondary metabolism.

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NMR and LC-MS-Based Metabolomics to Study Osmotic Stress in Lignan-Deficient Flax

Molecules ◽

10.3390/molecules26030767 ◽

2021 ◽

Vol 26 (3) ◽

pp. 767

Author(s):

Kamar Hamade ◽

Ophélie Fliniaux ◽

Jean-Xavier Fontaine ◽

Roland Molinié ◽

Elvis Otogo Nnang ◽

...

Keyword(s):

Stress Response ◽

Osmotic Stress ◽

Biosynthetic Pathway ◽

Potential Role ◽

Plant Secondary Metabolites ◽

Wild Type ◽

Osmotic Stress Response ◽

Transgenic Flax ◽

Insight Into

Lignans, phenolic plant secondary metabolites, are derived from the phenylpropanoid biosynthetic pathway. Although, being investigated for their health benefits in terms of antioxidant, antitumor, anti-inflammatory and antiviral properties, the role of these molecules in plants remains incompletely elucidated; a potential role in stress response mechanisms has been, however, proposed. In this study, a non-targeted metabolomic analysis of the roots, stems, and leaves of wild-type and PLR1-RNAi transgenic flax, devoid of (+) secoisolariciresinol diglucoside ((+) SDG)—the main flaxseed lignan, was performed using 1H-NMR and LC-MS, in order to obtain further insight into the involvement of lignan in the response of plant to osmotic stress. Results showed that wild-type and lignan-deficient flax plants have different metabolic responses after being exposed to osmotic stress conditions, but they both showed the capacity to induce an adaptive response to osmotic stress. These findings suggest the indirect involvement of lignans in osmotic stress response.

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Rox3 and Rts1 Function in the Global Stress Response Pathway in Baker's Yeast

Genetics ◽

10.1093/genetics/142.4.1083 ◽

1996 ◽

Vol 142 (4) ◽

pp. 1083-1093 ◽

Cited By ~ 8

Author(s):

Carlos C Evangelista ◽

Ana M Rodriguez Torres ◽

M Paullin Limbach ◽

Richard S Zitomer

Keyword(s):

Stress Response ◽

Heat Shock ◽

Osmotic Stress ◽

Regulatory Element ◽

Regulatory Region ◽

Mitogen Activated Protein Kinase ◽

Regulatory Subunit ◽

Temperature Sensitive ◽

Global Stress ◽

Rna Accumulation

Abstract Yeast respond to a variety of stresses through a global stress response that is mediated by a number of signal transduction pathways and the cis-acting STRE DNA sequence. The CYC7 gene, encoding iso-2-cytochrome c, has been demonstrated to respond to heat shock, glucose starvation, approach-to-stationary phase, and, as we demonstrate here, to osmotic stress. This response was delayed in a the hogl-Δ1 strain implicating the Hog1 mitogen-activated protein kinase cascade, a known component of the global stress response. Deletion analysis of the CYC7 regulatory region suggested that three STRE elements were each capable of inducing the stress response. Mutations in the ROX3 gene prevented CYC7 RNA accumulation during heat shock and osmotic stress. ROX3 RNA levels were shown to be induced by stress through a novel regulatory element. A selection for high-copy suppressors of a ROX3 temperature-sensitive allele resulted in the isolation of RTS1, encoding a protein with homology to the B′ regulatory subunit of protein phosphatase 2A0. Deletion of RTS1 caused temperature and osmotic sensitivity and increased accumulation of CYC7 RNA under all conditions. Over-expression of this gene caused increased CYC7 RNA accumulation in rox3 mutants but not in wild-type cells.

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Genome-wide transcriptional profiling and enrichment mapping reveal divergent and conserved roles of Sko1 in the Candida albicans osmotic stress response

Genomics ◽

10.1016/j.ygeno.2013.06.002 ◽

2013 ◽

Vol 102 (4) ◽

pp. 363-371 ◽

Cited By ~ 12

Author(s):

Dawn H. Marotta ◽

Andre Nantel ◽

Leonid Sukala ◽

Jennifer R. Teubl ◽

Jason M. Rauceo

Keyword(s):

Candida Albicans ◽

Stress Response ◽

Osmotic Stress ◽

Transcriptional Profiling ◽

Genome Wide ◽

Osmotic Stress Response

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Glycerol metabolism in rabbits

Canadian Journal of Biochemistry ◽

10.1139/o68-165 ◽

1968 ◽

Vol 46 (9) ◽

pp. 1107-1114 ◽

Cited By ~ 16

Author(s):

Jean Himms-Hagen

Keyword(s):

Turnover Rate ◽

Glycerol Kinase ◽

Rabbit Liver ◽

Constant Infusion ◽

Glycerol Dehydrogenase ◽

Glycerol Metabolism ◽

Utilization Rate ◽

Glycerol Concentration ◽

Glycerol Utilization ◽

Fractional Turnover

The endogenous rate of glycerol production in rabbits was measured by several techniques: constant infusion of 1,3-14C-glycerol or 2-3H-glycerol or unlabeled glycerol; single injection of 1,3-14C-glycerol or 2-3H-glycerol or unlabeled glycerol. The rate was 5.5–11.6 μmoles/kg per minute (9 rabbits). The mean fractional turnover rate was 0.0585 ± 0.0052. During infusion of noradrenaline together with 3H-glycerol, the fractional turnover rate was no different from that in the absence of noradrenaline. The maximum utilization rate of glycerol was 28.1 ± 1.40 μmoles/kg per minute. The glycerol space was 58.1% of body weight. The relationship of glycerol concentration to rate of glycerol utilization in the intact rabbit suggests the existence of an enzyme with a KM for glycerol of 0.33 × 10−3 M; the glycerol kinase of rabbit liver was found to have a KM for glycerol of 0.29 × 10−3 M. This enzyme could account for the disappearance of glycerol in the intact animal except that its Vmax is only 4% of that expected. Possible reasons for this are discussed. A glycerol dehydrogenase with a Vmax similar to that of the glycerol kinase also exists in rabbit liver; its KM for glycerol is so high (0.5 M) that it is unlikely to play a significant role in glycerol metabolism in the normal rabbit.

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