Search results for "complex"
showing 10 items of 5889 documents
Yeast karyopherins Kap123 and Kap95 are related to the function of the cell integrity pathway
2009
The characterization of mutant strains in the gene encoding karyopherin Kap123 has revealed several morphogenetic defects. Inactivation of KAP123 caused alterations in the actin cytoskeleton, resulting in hyperpolarization and resistance to the actin polymerization inhibitor latrunculin B. In fact, the level of actin filaments is increased in kap123 mutant cells. In addition to the defect in actin cytoskeleton, the kap123 mutant cells showed a weakened cell wall, cell lysis and a growth defect in either the presence of sodium dodecyl sulfate or at high temperatures, which is alleviated by osmotic stabilizers. These defects in cell integrity and the actin cytoskeleton suggested a relationshi…
Rot1 plays an antagonistic role to Clb2 in actin cytoskeleton dynamics throughout the cell cycle.
2007
ROT1 is an essential gene whose inactivation causes defects in cell cycle progression and morphogenesis in budding yeast. Rot1 affects the actin cytoskeleton during the cell cycle at two levels. First, it is required for the maintenance of apical growth during bud growth. Second, Rot1 is necessary to polarize actin cytoskeleton to the neck region at the end of mitosis; because of this defect, rot1 cells do not properly form a septum to complete cell division. The inability to polarize the actin cytoskeleton at the end of mitosis is not due to a defect in the recruitment of the polarisome scaffold protein Spa2 or the actin cytoskeleton regulators Cdc42 and Cdc24 in the neck region. Previous …
The MAPK Hog1 recruits Rpd3 histone deacetylase to activate osmoresponsive genes
2003
Regulation of gene expression by mitogen-activated protein kinases (MAPKs) is essential for proper cell adaptation to extracellular stimuli. Exposure of yeast cells to high osmolarity results in rapid activation of the MAPK Hog1, which coordinates the transcriptional programme required for cell survival on osmostress. The mechanisms by which Hog1 and MAPKs in general regulate gene expression are not completely understood, although Hog1 can modify some transcription factors. Here we propose that Hog1 induces gene expression by a mechanism that involves recruiting a specific histone deacetylase complex to the promoters of genes regulated by osmostress. Cells lacking the Rpd3-Sin3 histone deac…
Physical and Genetic Interactions Link the Yeast Protein Zds1p with mRNA Nuclear Export
2005
Eukaryotic gene expression requires the export of mRNA from the nucleus to the cytoplasm. The DEAD box protein Dbp5p is an essential export factor conserved from yeast to man. A fraction of Dbp5p forms a complex with nucleoporins of the cytoplasmic filaments of the nuclear pore complex. Gfd1p was identified originally as a multicopy suppressor of the rat8-2 ts allele of DBP5. Here we reported that Dbp5p and Gfd1p interact with Zds1p, a protein previously identified as a multicopy suppressor in several yeast genetic screens. By using the two-hybrid system, we showed that Zds1p interacts in vivo with both Gfd1p and Dbp5p. In vitro binding experiments revealed that Gfd1p and Dbp5p bind directl…
Ubiquitin ligase Rsp5p is involved in the gene expression changes during nutrient limitation inSaccharomyces cerevisiae
2009
Rsp5p is an essential ubiquitin ligase involved in many different cellular events, including amino acid transporters degradation, transcription initiation and mRNA export. It plays important role in both stress resistance and adaptation to the change of nutrients. We have found that ubiquitination machinery is necessary for the correct induction of the stress response SPI1 gene at the entry of the stationary phase. SPI1 is a gene whose expression is regulated by the nutritional status of the cell and whose deletion causes hypersensitivity to various stresses, such as heat shock, alkaline stress and oxidative stress. Its regulation is mastered by Rsp5p, as mutations in this gene lead to a lo…
Exploratory analysis of safety data and their interrelation with flight trajectories and network metrics
2013
This paper presents an exploratory analysis of the correlation between different network metrics and safety events. The objective is to develop analysis methods and indicators that relate the network structure with safety events. In particular by using data gathered with an automatic tool developed by EUROCONTROL and a database of traffic data, we measured the correlations between the classical metrics of the airspace network, especially the network of navigation points, and the occurrence of Short Term Conflicts Alerts (STCA). The results obtained are not univocal; correlation between STCA occurrences and classical network metrics are present but the correlation coefficient is around 0.7. …
SALMO and S3M: A Saliva Model and a Single Saliva Salt Model for Equilibrium Studies.
2014
A model of synthetic saliva (SALMO, SALiva MOdel) is proposed for its use as standard medium inin vitroequilibrium and speciation studies of real saliva. The concentrations come out from the literature analysis of the composition of both real saliva and synthetic saliva. The chief interactions of main inorganic components of saliva, as well as urea and amino acids, are taken into account on the basis of a complex formation model, which also considers the dependence of the stability constants of these species on ionic strength and temperature. These last features allow the modelling of the speciation of saliva in different physiological conditions deriving from processes like dilution, pH, a…
DNA Oxidation Photoinduced by Norharmane Rhenium(I) Polypyridyl Complexes: Effect of the Bidentate N,N′-Ligands on the Damage Profile
2018
Re(I)--polypyridyl complexes have interesting and distinctive photochemical and photosensitizing properties. This work describes the capability to induce (or photoinduce) DNA damage of three Re(I)-complexes with a naturally occurring alkaloid called norharmane (nHo) as ligand: [Re(CO)₃ (nHo)(L)]CF₃ SO₃ where L=2,2'-bipyridine (ReBpy), phenanthroline (RePhen) or dipyrido[3,2-a:2',3'-c]phenazine (ReDppz). The interaction of the complexes with DNA was investigated by steady-state and time-resolved spectroscopy. Data show that the mode and strength of interaction depend on the chemical structure of the bidentate ligand. The complexes show a major static contribution to the overall interaction, …
Oral immunization with HCV-NS3-transformed Salmonella: induction of HCV-specific CTL in a transgenic mouse model.
2001
Abstract Background & Aims: The ability to induce cytotoxic T cells is considered an important feature of a candidate hepatitis C virus (HCV) vaccine. We used an oral immunization strategy with attenuated HCV-NS3–transformed Salmonella typhimurium to deliver DNA directly to the gut-associated lymphoid tissue. Methods: HLA-A2.1 transgenic mice were immunized once with transformed attenuated Salmonella . HCV-specific CD8 + T cells were analyzed in vitro as well as in vivo by challenge of mice with recombinant HCV-NS3 vaccinia virus. Results: Salmonella (10 8 colony-forming units; 20 μg plasmid DNA) induced cytotoxic and IFN-γ–producing CD8 + T cells specific for the immunodominant epitope NS3…
Long-term survival of pathogenic and sanitation indicator bacteria in experimental biowaste composts
2005
ABSTRACT For economic, agricultural, and environmental reasons, composting is frequently used for organic waste recycling. One approach to limiting the potential risk from bacterial food-borne illnesses is to ensure that soil amendments and organic fertilizers are disinfected. However, more knowledge concerning the microbiological safety of composted substrates other than sludge and manure is necessary. Experimental in-vessel biowaste composts were used to study the survival of seeded Listeria monocytogenes , Salmonella enterica subsp. enterica serotype Enteritidis, and Escherichia coli . Four organic waste mixtures, containing various proportions of paper and cardboard, fruits and vegetabl…