ABSTRACT Conventional tools for elucidating gene function are relatively scarce in Candida albicans , the most prevalent human fungal pathogen. To this end, we developed a convenient system to control expression C. by tetracycline-regulatable (TR) promoters. When sea pansy Renilla reniformis luciferase ( RLUC1 ) was placed under of system, doxycycline (DOX) inhibited activity almost completely. In absence DOX, induced express at level 400- 1,000-fold higher than that presence DOX. The same...

Proper protein folding in the endoplasmic reticulum (ER) is vital all eukaryotes. When misfolded proteins accumulate ER lumen, transmembrane kinase/endoribonuclease Ire1 initiates splicing of HAC1 mRNA to generate bZIP transcription factor Hac1, which subsequently activates its target genes increase protein-folding capacity ER. This cellular machinery, called unfolded response (UPR), believed be an evolutionarily conserved mechanism In this study, we comprehensively characterized mutant...

In the pathogenic yeast Candida glabrata, gene targeting to generate knockouts and "knockins" is a potentially powerful method for analysis of function. Its importance increased after C. glabrata genome sequence project, but progress in field hampered by inefficient mechanisms targeting. With use 40-bp homologous flanking DNA, no was identified. To address this issue, YKU80 disrupted, leading an increase efficiency 5.1% using DNA. harness beneficial effects inactivation on frequency without...

Zn[2]-Cys[6] binuclear transcription factors Upc2p and Ecm22p regulate the expression of genes involved in ergosterol biosynthesis exogenous sterol uptake Saccharomyces cerevisiae. We identified two UPC2/ECM22 homologues pathogenic fungus Candida glabrata which we designated CgUPC2A CgUPC2B. The contribution these to homeostasis was investigated. Cells that lack (upc2AΔ) exhibited enhanced susceptibility inhibitors, fluconazole lovastatin, whereas upc2BΔ-mutant cells were as susceptible...

Multidrug resistance in the pathogenic fungus Candida glabrata is a growing global threat. Here, we study mechanisms of multidrug this pathogen. Exposure C. cells to micafungin (an echinocandin) leads isolation mutant exhibiting echinocandin and azole antifungals. The drug-resistant phenotype due non-synonymous mutation (R70H) gene IPI1, which involved pre-rRNA processing. Azole ipi1R70H depends on Pdr1 transcription factor, regulates expression transporters. Ipi1 protein physically...

The uptake of endogenous sterol from serum may allow Candida glabrata to survive azole treatment. This study aims determine the contribution a transporter that alters fluconazole sensitivity in presence serum. Bioinformatic analysis predicted CgAUS1 as C. orthologue Saccharomyces cerevisiae transporters AUS1 and PDR11. To investigate whether gene has activity, we investigated effects an deletion on growth tetracycline-regulatable ERG9 strain (tet-ERG9aus1), wherein expression is turned off...

Candida glabrata, a haploid budding yeast, is the cause of severe systemic infections in immune-compromised hosts. The amount free iron supplied to C. glabrata cells during severely limited by iron-chelating proteins such as transferrin. Thus, iron-deficiency response thought play important roles their survival inside host's body. In this study, we found that mitophagy was induced under iron-depleted conditions, and disruption gene homologous ATG32, which responsible for Saccharomyces...

ObjectivesThe ability of opportunistic pathogenic Candida species to persist and invade specific niches in the human host depends on their resistance natural growth inhibitors antifungal therapy. This work describes role glabrata drug:H+ antiporter CgTpo3 (ORF CAGL0I10384g) this context.

To identify chemoresistance‐related genes of gastric cancer, we utilized cDNA microarray technology. Thirty‐five cancer specimens surgically resected at our institute between 1998 and 1999 were studied for quantification expression 6300 by means oligonucleotide methods, the results evaluated in comparison with chemoresistance specimens, which was determined MTT (tetrazolium‐based 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay. Inhibition rates (IR) cisplatin (DDP),...

A system for controlling gene expression was established in the pathogenic fungus Candida glabrata to elucidate physiological functions of genes. To control interest, C. cells were first transformed with plasmid carrying tetracycline repressor-transactivator fusion tetR::GAL4, then DNA fragment containing controllable cassette, operator chimeric promoter (tetO::ScHOP1). The peptide elongation factor 3 (CgTEF3) and topoisomerase II (CgTOP2) genes from cloned their assessed using this system....

Summary During disseminated infection by the opportunistic pathogen C andida glabrata , uptake of sterols such as serum cholesterol may play a significant role during pathogenesis. The ATP ‐binding cassette transporter A us1p is thought to function sterol importer and in this study, we show that exogenous occurred under anaerobic conditions wild‐type cells . but not AUS 1 ‐deleted mutant ( aus1 Δ) cells. In aerobic cultures, growth inhibition fluconazole was prevented presence serum,...

ABSTRACT Squalene synthase (farnesyl-diphosphate farnesyltransferase, EC 2.5.1.21 ) is the first committed enzyme of sterol biosynthesis pathway. Inhibitors this have been intensively studied as potential antifungal agents. To assess effect deactivating squalene on growth fungi in mice, we isolated ( ERG9 gene from pathogenic fungus Candida glabrata and generated strains which CgERG9 was under control tetracycline-regulatable promoter. Depletion by doxycycline (DOX), a derivative...

Chronic infection with hepatitis B or C virus (HBV HCV) is the most clearly established risk factor for hepato-cellular carcinoma (HCC). One type of HCC (non-B, non-C HCC) also appears to develop in patients negative both HBV and HCV. Using a supervised learning method, we investigated gene expression 11 non-B, HCCs high-density oligonucleotide microarrays, compared patterns those HBV-infected (B-type HCCs) HCV-infected (C-type previous dataset. Our selection identified 112 64 genes that...

We investigated the cellular function of Msi3p, belonging to heat shock protein 70 family, in Candida albicans. The mutant strain tetMSI3 was generated, which MSI3 controlled by a tetracycline-repressive promoter, because there is evidence suggest that an essential gene. expression level doxycycline (DOX) and compared its phenotype with control promoter wild-type copy MSI3. results indicated for cell growth. In addition, all tetMSI3-infected mice survived after DOX administration. Drug...

Vacuolar H+-ATPase (V-ATPase) is responsible for the acidification of eukaryotic intracellular compartments and plays an important role in oxidative stress response (OSR), but its molecular bases are largely unknown. Here, we investigated how V-ATPase involved OSR by using a strain lacking VPH2, which encodes assembly factor V-ATPase, pathogenic fungus Candida glabrata. The loss Vph2 resulted increased H2O2 sensitivity reactive oxygen species (ROS) level independently mitochondrial...

To clarify the role of p53 in 22 hepatitis C virus (HCV)‐infected hepatocellular carcinomas (HCCs), we compared gene expression profiles HCCs with wild‐type (wt‐p53) ( n =17) and those mutant‐type (mt‐p53) =5) by oligonucleotide microarray analysis. Among 83 ‐related genes identified a supervised learning method, 25 were underexpressed, 58 overexpressed mt‐p53 wt‐p53 HCCs. With computer search, consensus p53‐binding sequences 3‐kb region upstream translation initiation site 59 genes,...

The uptake of cholesterol from the host is closely linked to proliferation pathogenic fungi and protozoa during infection. For some , an important strategy for decreasing susceptibility antifungals that inhibit ergosterol biosynthesis. In this study, we show Candida glabrata ERG25 which encodes enzyme demethylates 4,4-dimethylzymosterol, required serum. Based on screening C. conditional knockdown mutants each gene involved in biosynthesis, was found decrease lethality infected mice. impairs...

ABSTRACT Sterol 14α-demethylase ( ERG11 ) is the target enzyme of azole antifungals that are widely used for treatment fungal infections. Candida glabrata known to be less susceptible fluconazole than most albicans strains, and incidence C. infection has been increasing mostly in conjunction with use antifungals. Recently, it reported can rescue defect ergosterol biosynthesis by incorporating cholesterol from serum. To explore effect inactivating Erg11p , we generated mutant strains which...

Vacuolar proton-translocating ATPase (V-ATPase) is located in fungal vacuolar membranes. It involved multiple cellular processes, including the maintenance of intracellular ion homeostasis by maintaining acidic pH within cell. The importance V-ATPase virulence has been demonstrated several pathogenic fungi, Candida albicans. However, it remains to be determined clinically important pathogen glabrata. Increasing multidrug resistance C. glabrata becoming a critical issue clinical setting. In...

Quorum sensing through farnesol, a quorum molecule, regulates virulence and morphogenesis in Candida albicans. Farnesol high cell density of C. albicans repress hyphal formation minimal medium containing N-acetyl-D-glucosamine. Global transcription profiling at an early stage by the N-acetyl-D-glucosamine was analyzed. Twenty-two total 53 genes responded to both farnesol density. From silico analysis previous published data, nine these including those encoding amino acid biosynthesis were...

A mechanism for the acquisition of high-level echinocandin resistance in Candida glabrata was investigated. FKS mutants were constructed to: determine whether clinically significant micafungin requires a hot-spot mutation FKS1 and premature stop codon FKS2, as observed clinical isolate; select variants with reduced susceptibility locate mutations genes; assess roles FKS2. panel using micafungin-susceptible parents by site-directed mutagenesis. Drug susceptibility, gene expression glucan...