26 research outputs found
Phenotype of mutants in the PI(3,5)P<sub>2</sub> pathway under screening conditions.
<p>(A) BY4741 <i>Δfab1</i> and BY4741 <i>Δfig4</i> cells were cultivated and subjected to vacuole fragmentation under screening conditions in diluted YPD. Pictures show an overlay of the fluorescence and brightfield channels. (B) Metabolic pathways leading to the synthesis of PI(3,5)P<sub>2</sub>. Steps for which a gene deletion led to strong or moderate deficiency in vacuole fragmentation are indicated in red/bold.</p
Adaptin- and cytoskeleton-related mutants.
<p>Adaptin- and cytoskeleton-related mutants.</p
Identified mutants in triglyceride metabolism.
<p>Identified mutants in triglyceride metabolism.</p
The in vivo fragmentation assay under screening conditions.
<p>(A) The cells were grown overnight in 96-well plates in HC-Leu<sup>-</sup> medium to an OD<sub>600</sub><2. They were diluted 10-fold in YPD, stained with 20 µM FM4-64 for 1 hour, centrifuged and resuspended in YPD, HC or YPD diluted 5-fold with water (diluted YPD). After shaking for 2 hrs at 27°C, cells were transferred into optical 96-well plates. Fragmentation was induced by supplementing the suspension with 0.4 M NaCl. After 10 min of incubation at room temperature, cells were analyzed by fluorescence microscopy. Note that the screen was performed on a non-confocal microscope. Fragmentation was easier to judge on the microscope than on the photos, due to the possibility to focus through the sample in the z-direction. (B) Examples illustrating the scoring of the fragmentation defect. Samples sho pictures from cells after incubation with salt as in A.</p
Mutants related to vacuolar function, biogenesis and inheritance.
<p>Mutants related to vacuolar function, biogenesis and inheritance.</p
Identified mutants affecting processes known to be involved in vacuole fragmentation: PI(3,5)P<sub>2</sub> metabolism, vacuole acidification and TOR signaling.
<p>Identified mutants affecting processes known to be involved in vacuole fragmentation: PI(3,5)P<sub>2</sub> metabolism, vacuole acidification and TOR signaling.</p
Exploring potential socio-ecological impacts of changes to the Loliondo Gamed Controlled Area, Northern Tanzania: the case of the pastoral village Ololosokwan
<p>Recent plans to alter the Loliondo Game Controlled Area (GCA), a nature conservation area located in Northern Tanzania, would result in substantial reduction of rangelands in the region. We quantify the current and hypothetical levels of the aboveground Human Appropriation of Net Primary Production (aHANPP) in one of the affected villages, and estimate the maximum exploitability rate of rangelands by livestock in the region. We find that the current aHANPP of the village amounts to 34–38% of the potential productivity, which could increase to 59–67% due to the altered GCA. On rangelands, livestock-induced aHANPP would increase from the current level of 30–34% to 54–61%, which is far above a maximum exploitability rate of 40–41%. Our results reveal that the intended changes to the Loliondo GCA will severely affect the current livelihood strategy of the Maasai, which is based on pastoralism.</p
Test-Methods on the Test-Bench: A Comparison of Complete Exhaust and Exhaust Particle Extracts for Genotoxicity/Mutagenicity Assessment
With
the growing number of new exhaust after-treatment systems,
fuels and fuel additives for internal combustion engines, efficient
and reliable methods for detecting exhaust genotoxicity and mutagenicity
are needed to avoid the widespread application of technologies with
undesirable effects toward public health. In a commonly used approach,
organic extracts of particulates rather than complete exhaust is used
for genotoxicity/mutagenicity assessment, which may reduce the reliability
of the results. In the present study, we assessed the mutagenicity
and the genotoxicity of complete diesel exhaust compared to an organic
exhaust particle extract from the same diesel exhaust in a bacterial
and a eukaryotic system, that is, a complex human lung cell model.
Both, complete exhaust and organic extract were found to act mutagenic/genotoxic,
but the amplitudes of the effects differed considerably. Furthermore,
our data indicate that the nature of the mutagenicity may not be identical
for complete exhaust and particle extracts. Because in addition, differences
between the responses of the different biological systems were found,
we suggest that a comprehensive assessment of exhaust toxicity is
preferably performed with complete exhaust and with biological systems
representative for the organisms and organs of interest (i.e., human
lungs) and not only with the Ames test
The Q<sub>bc</sub>R-complex stability does not depend on trans-SNARE interactions.
<p>Isolated vacuoles were either fused under standard condition or diluted up to a density of 100 µg/ml prior to the addition of salt and ATP. After incubation for 5 min at 27°C, the standard fusion reaction (500 µg/ml) was diluted to the same density of 100 µg/ml, and 3 mM EDTA was added. After addition of Triton X-100 to a final concentration of 0.5% and brief centrifugation, Nyv1 was precipitated as described above. We found no difference in Q<sub>bc</sub>R-complex stability between diluted and non-diluted vacuoles.</p