Search results for "Wester"
showing 10 items of 1157 documents
Functional Connection Between the Clb5 Cyclin, the Protein Kinase C Pathway and the Swi4 Transcription Factor in Saccharomyces cerevisiae
2005
Abstract The rsf12 mutation was isolated in a synthetic lethal screen for genes functionally interacting with Swi4. RSF12 is CLB5. The clb5 swi4 mutant cells arrest at G2/M due to the activation of the DNA-damage checkpoint. Defects in DNA integrity was confirmed by the increased rates of chromosome loss and mitotic recombination. Other results suggest the presence of additional defects related to morphogenesis. Interestingly, genes of the PKC pathway rescue the growth defect of clb5 swi4, and pkc1 and slt2 mutations are synthetic lethal with clb5, pointing to a connection between Clb5, the PKC pathway, and Swi4. Different observations suggest that like Clb5, the PKC pathway and Swi4 are in…
Functional distinction between Cln1p and Cln2p cyclins in the control of the Saccharomyces cerevisiae mitotic cycle.
2004
Abstract Cln1p and Cln2p are considered as equivalent cyclins on the basis of sequence homology, regulation, and functional studies. Here we describe a functional distinction between the Cln1p and Cln2p cyclins in the control of the G1/S transition. Inactivation of CLN2, but not of CLN1, leads to a larger-than-normal cell size, whereas overexpression of CLN2, but not of CLN1, results in smaller-than-normal cells. Furthermore, mild ectopic expression of CLN2, but not of CLN1, suppresses the lethality of swi4swi6 and cdc28 mutant strains. In the absence of Cln1p, the kinetics of budding, initiation of DNA replication, and activation of the Start-transcription program are not affected; by cont…
Trx2p-dependent Regulation of Saccharomyces cerevisiae Oxidative Stress Response by the Skn7p Transcription Factor under Respiring Conditions
2013
The whole genome analysis has demonstrated that wine yeasts undergo changes in promoter regions and variations in gene copy number, which make them different to lab strains and help them better adapt to stressful conditions during winemaking, where oxidative stress plays a critical role. Since cytoplasmic thioredoxin II, a small protein with thiol-disulphide oxidoreductase activity, has been seen to perform important functions under biomass propagation conditions of wine yeasts, we studied the involvement of Trx2p in the molecular regulation of the oxidative stress transcriptional response on these strains. In this study, we analyzed the expression levels of several oxidative stress-related…
The ATC1 gene encodes a cell wall-linked acid trehalase required for growth on trehalose in Candida albicans.
2004
After screening a Candida albicans genome data base, the product of an open reading frame (IPF 19760/CA2574) with 41% identity to Saccharomyces cerevisiae vacuolar acid trehalase (Ath1p) was identified and named Atc1p. The deduced amino acid sequence shows that Atc1p contains an N-terminal hydrophobic signal peptide and 20 potential sites for N-glycosylation. C. albicans homozygous mutants that lack acid trehalase activity were constructed by gene disruption at the two ATC chromosomal alleles. Analysis of these null mutants shows that Atc1p is localized in the cell wall and is required for growth on trehalose as a carbon source. An Atc1p endowed with acid trehalase activity was obtained by …
Molecular cloning and characterization of a Candida albicans gene coding for cytochrome c haem lyase and a cell wall-related protein.
1998
Immunoscreening of a Candida albicans cDNA library with a monoclonal antibody (mAb 4C12) recognizing an epitope present in high-molecular-weight mannoprotein (HMWM) components specific for the mycelial cell walls (a 180 kDa component and a polydispersed 260 kDa species) resulted in the isolation of the gene CaCYC3 encoding for cytochrome c haem lyase (CCHL). The CaCYC3 gene was transcribed preferentially in mycelial cells in which two mRNA transcripts of 0.8 and 1 kb were found. The nucleotide and the deduced amino acid sequences of this gene displayed 45% homology and 46% identity, respectively, to the Saccharomyces cerevisiae CYC3 gene and shared common features with other reported genes …
Expression of human estrogen sulfotransferase in Salmonella typhimurium: differences between hHST and hEST in the enantioselective activation of 1-hy…
1998
Various human sulfotransferases (hP-PST, hM-PST, hHST) and rat sulfotransferases (rPST-IV, rHSTa) have already been expressed in Ames' Salmonella strains (in particular in TA1538). Now a further strain, TA1538-hEST, which expresses the human estrogen sulfotransferase (hEST), has been constructed. This strain activated the primary benzylic alcohol 1-hydroxymethylpyrene (1-HMP) and the secondary benzylic alcohol 1-hydroxyethylpyrene (1-HEP) to mutagens. Human sulfotransferases hEST and hHST both activated 1-HEP, but they differed substantially in their enantioselectivity for this compound.
Increase of sensitivity and validity of the SOS/umu-test after replacement of the beta-galactosidase reporter gene with luciferase.
1998
The SOS/umu-test with Salmonella typhimurium TA1535/pSK1002 as tester strain is a rapid and valuable bacterial assay for screening of umuC-dependent mutagenic potential of chemical compounds and chemicals relevant to environmental pollution. The initial assay was modified by replacing the beta-galactosidase reporter gene with luciferase. Thereby, the sensitivity of the umu-test was increased significantly and the susceptibility to intensively coloured solutions was reduced. The alternative enzyme assay in the modified umu-test (umu-Luc) represents an independent method which allows to confirm the colorimetric results obtained with the original SOS/umu-test system (umu-Gal) by measuring the …
Inhibition of the pro-inflammatory mediators' production and anti-inflammatory effect of the iridoid scrovalentinoside.
2007
We have studied scrovalentinoside, an iridoid with anti-inflammatory properties isolated from Scrophularia auriculata ssp. pseudoauriculata, as an anti-inflammatory agent in different experimental models of delayed-type hypersensitivity. We found that scrovalentinoside reduced the edema induced by oxazolone at 0.5 mg/ear and sheep red blood cells at 10 mg/kg. The observed effect occurred during the last phase or inflammatory response; during the earlier phase or induction of the delayed-type hypersensitivity reaction, no significant activity was noted. Thus, scrovalentinoside reduced both the edema and cell infiltration in vivo and reduced lymphocyte proliferation in vitro, affecting the cy…
Localization of HSP70, Cdc2, and cyclin B in sea urchin oocytes in non-stressed conditions.
2003
In Paracentrotus lividus embryos, a Mediterranean sea urchin species, HSP70 is present in all the cells. During cell division it localizes under normal growth conditions on the centrosomes and on the whole isolated mitotic apparatus. Now, in situ hybridization, Western blot analyses, and immunohistochemistry show that the HSP70 mRNA is present in both small and large P. lividus oocytes, that all four isoforms of HSP70 can be found also in the oocytes, and that a certain amount of HSP70 localizes on asters and spindles during polar body formation. Moreover, two representative cell-cycle related proteins, cyclin B, and Cdc2, are present both in small and large oocytes, concentrating in the ge…