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41.
Dynamics of the yeast transcriptome during wine fermentation reveals a novel fermentation stress response 总被引:3,自引:0,他引:3
Marks VD Ho Sui SJ Erasmus D van der Merwe GK Brumm J Wasserman WW Bryan J van Vuuren HJ 《FEMS yeast research》2008,8(1):35-52
In this study, genome-wide expression analyses were used to study the response of Saccharomyces cerevisiae to stress throughout a 15-day wine fermentation. Forty per cent of the yeast genome significantly changed expression levels to mediate long-term adaptation to fermenting grape must. Among the genes that changed expression levels, a group of 223 genes was identified, which was designated as fermentation stress response (FSR) genes that were dramatically induced at various points during fermentation. FSR genes sustain high levels of induction up to the final time point and exhibited changes in expression levels ranging from four- to 80-fold. The FSR is novel; 62% of the genes involved have not been implicated in global stress responses and 28% of the FSR genes have no functional annotation. Genes involved in respiratory metabolism and gluconeogenesis were expressed during fermentation despite the presence of high concentrations of glucose. Ethanol, rather than nutrient depletion, seems to be responsible for entry of yeast cells into the stationary phase. 相似文献
42.
Biodiversity can provide insurance against environmental change, but only if species differ in their response to environmental conditions (response diversity). Wild bees provide pollination services to wild and crop plants, and response diversity might insure this function against changing climate. To experimentally test the hypothesis that bee species differ in their response to increasing winter temperature, we stored cocoons of nine bee species at different temperatures during the winter (1.5–9.5 °C). Bee species differed significantly in their responses (weight loss, weight at emergence and emergence date). The developmental stage during the winter explained some of these differences. Bee species overwintering as adults generally showed decreased weight and earlier emergence with increasing temperature, whereas bee species overwintering in pre-imaginal stages showed weaker or even opposite responses. This means that winter warming will likely affect some bee species negatively by increasing energy expenditure, while others are less sensitive presumably due to different physiology. Likewise, species phenologies will respond differently to winter warming, potentially affecting plant–pollinator interactions. Responses are not independent of current flight periods: bees active in spring will likely show the strongest phenological advances. Taken together, wild bee diversity provides response diversity to climate change, which may be the basis for an insurance effect. 相似文献
43.
Hans -Ortwin Nalbach Jochen Zeil Luise Forzin 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1989,165(5):643-649
1. | We recorded compensatory eye stalk movements in response to pitch and roll stimulation of the visual, statocyst, and leg-proprioceptive systems in different species of crabs (Carcinus maenas, Heloecius cordiformis, Pachygrapsus marmoratus) (Fig. 2). |
2. | The relative contribution of visual, statocyst and leg-proprioceptive inputs to eye stabilization in space varies greatly among different species (Fig. 3). |
3. | We suggest that for stabilizing the eyes in space, the contribution of various sensory inputs in different species of crabs correspond to the availability of cues in their habitat. Semiterrestrial crabs living in a habitat with well defined and predictable visual geometry stabilize their eye stalks mainly by visual cues. Crabs living on solid substrate make strong use of leg proprioceptive input. Swimming crabs, and other predominantly aquatic crabs, rely mainly on their statocysts. |
44.
María-José Coronado Götz Hensel Sylvia Broeders Ingrid Otto Jochen Kumlehn 《Acta Physiologiae Plantarum》2005,27(4):591-599
Barley transformation mediated by Agrobacterium tumefaciens is routinely performed in a number of laboratories. However, elimination of selectable marker genes and formation of plants
homozygous for the transgene via conventional segregation is laborious and time-consuming. Here we suggest a concept that
includes the production of primary transgenic plants via infection of immature embryos with A. tumefaciens followed by androgenetic generation of a segregating population of entirely homozygous plants. Selectable marker-free, truebreeding
plants carrying a single-opy transgene integrant may thus be efficiently and rapidly obtained. However, amenability to Agrobacterium-mediated transformation as well as androgenetic potential is genotype-dependent. Efficient genetic transformation by infection
of immature embryos is so far confined to the spring type cultivar ‘Golden Promise’ which, however, turned out to be recalcitrant
in pollen embryogenesis. To facilitate androgenetic generation of homozygous segregants from primary transformants, we have
established a method for embryogenic pollen culture in cv. Golden Promise that includes conventional cold-treatment and subsequent
preculture of immature pollen under starvation conditions prior to transfer to complete nutrient medium. Further we show that
conditioning of the pollen culture medium by co-culture of immature wheat pistils as well as addition of pistil-preconditioned
medium considerably support androgenetic development. Employment of the established method using immature pollen of primary
transgenic plants demonstrates that selectable marker-free, true-breeding transgenic progeny can be rapidly obtained pursuing
the concept proposed. The protocol presented will be useful in functional genomics as well as in molecular breeding approaches. 相似文献
45.
Wei X Schneider JG Shenouda SM Lee A Towler DA Chakravarthy MV Vita JA Semenkovich CF 《The Journal of biological chemistry》2011,286(4):2933-2945
Endothelial dysfunction leads to lethal vascular complications in diabetes and related metabolic disorders. Here, we demonstrate that de novo lipogenesis, an insulin-dependent process driven by the multifunctional enzyme fatty-acid synthase (FAS), maintains endothelial function by targeting endothelial nitric-oxide synthase (eNOS) to the plasma membrane. In mice with endothelial inactivation of FAS (FASTie mice), eNOS membrane content and activity were decreased. eNOS and FAS were physically associated; eNOS palmitoylation was decreased in FAS-deficient cells, and incorporation of labeled carbon into eNOS-associated palmitate was FAS-dependent. FASTie mice manifested a proinflammatory state reflected as increases in vascular permeability, endothelial inflammatory markers, leukocyte migration, and susceptibility to LPS-induced death that was reversed with an NO donor. FAS-deficient endothelial cells showed deficient migratory capacity, and angiogenesis was decreased in FASTie mice subjected to hindlimb ischemia. Insulin induced FAS in endothelial cells freshly isolated from humans, and eNOS palmitoylation was decreased in mice with insulin-deficient or insulin-resistant diabetes. Thus, disrupting eNOS bioavailability through impaired lipogenesis identifies a novel mechanism coordinating nutritional status and tissue repair that may contribute to diabetic vascular disease. 相似文献
46.
47.
Online measurement of the respiratory activity in shake flasks enables the identification of cultivation phases and patterns indicating recombinant protein production in various Escherichia coli host strains 下载免费PDF全文
Nina Ihling Natalie Bittner Sylvia Diederichs Maximilian Schelden Anna Korona Georg Theo Höfler Alexander Fulton Karl‐Erich Jaeger Kohsuke Honda Hisao Ohtake Jochen Büchs 《Biotechnology progress》2018,34(2):315-327
Escherichia coli is commonly used for recombinant protein production with many available host strains. Screening experiments are often performed in batch mode using shake flasks and evaluating only the final product concentration. This conventional approach carries the risk of missing the best strain due to limited monitoring capabilities. Thus, this study focuses on investigating the general suitability of online respiration measurement for selecting expression hosts for heterologous protein production. The oxygen transfer rate (OTR) for different T7‐RNA polymerase‐dependent Escherichia coli expression strains was compared under inducing and noninducing conditions. As model enzymes, a lipase A from Bacillus subtilis (BSLA) and a 3‐hydroxybutyryl‐CoA dehydrogenase from Thermus thermophilus (HBD) were chosen. Four strains were compared during expression of both enzymes in autoinduction medium. Additionally, four strains were compared during expression of the BSLA with IPTG induction. It was found that the metabolic burden during recombinant protein production induces a phase of constant OTR, while undisturbed cell growth with no or little product formation is indicated by an exponential increase. This pattern is independent of the host strain, expressed enzyme, and induction method. Furthermore, the OTR gives information about carbon source consumption, biomass formation, and the transition from production to noninduced second growth phase, thereby ensuring a fair comparison of different strains. In conclusion, online monitoring of the respiration activity is suited to qualitatively identify, if a recombinant protein is produced by a strain or not. Furthermore, laborious offline sampling is avoided. Thus, the technique is easier and faster compared to conventional approaches. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:315–327, 2018 相似文献
48.
Heinz Tiedemann Jochen Born Hildegard Tiedemann 《Development genes and evolution》1972,171(2):160-169
Summary A morphogenetic factor which induces inTriturus gastrula ectoderm tissues which are derived from mesoderm and endoderm has been extracted from chicken and amphibian embryos. The factor which is protein in nature has been obtained from chicken embryos in a highly purified state.The biological activity of the chicken factor is partially inhibited when the factor is combined with chicken DNA or sonicated chicken DNA.When the 3H-labelled factor is combined with sonicated DNA and then centrifuged on a sucrose gradient the factor migrates in part with the DNA. This indicates that the factor is bound to DNA.The inferences from these results are discussed with regard to the possible mechanism of action of the factor and the molecular mechanism of differentiation. 相似文献
49.
Mapping DNA damage‐dependent genetic interactions in yeast via party mating and barcode fusion genetics 下载免费PDF全文
J Javier Díaz‐Mejía Albi Celaj Joseph C Mellor Atina Coté Attila Balint Brandon Ho Pritpal Bansal Fatemeh Shaeri Marinella Gebbia Jochen Weile Marta Verby Anna Karkhanina YiFan Zhang Cassandra Wong Justin Rich D'Arcy Prendergast Gaurav Gupta Sedide Öztürk Daniel Durocher Grant W Brown Frederick P Roth 《Molecular systems biology》2018,14(5)
Condition‐dependent genetic interactions can reveal functional relationships between genes that are not evident under standard culture conditions. State‐of‐the‐art yeast genetic interaction mapping, which relies on robotic manipulation of arrays of double‐mutant strains, does not scale readily to multi‐condition studies. Here, we describe barcode fusion genetics to map genetic interactions (BFG‐GI), by which double‐mutant strains generated via en masse “party” mating can also be monitored en masse for growth to detect genetic interactions. By using site‐specific recombination to fuse two DNA barcodes, each representing a specific gene deletion, BFG‐GI enables multiplexed quantitative tracking of double mutants via next‐generation sequencing. We applied BFG‐GI to a matrix of DNA repair genes under nine different conditions, including methyl methanesulfonate (MMS), 4‐nitroquinoline 1‐oxide (4NQO), bleomycin, zeocin, and three other DNA‐damaging environments. BFG‐GI recapitulated known genetic interactions and yielded new condition‐dependent genetic interactions. We validated and further explored a subnetwork of condition‐dependent genetic interactions involving MAG1, SLX4, and genes encoding the Shu complex, and inferred that loss of the Shu complex leads to an increase in the activation of the checkpoint protein kinase Rad53. 相似文献
50.
Kristof Notelaers Susana Rocha Rik Paesen Nina Swinnen Jeroen Vangindertael Jochen C. Meier Jean-Michel Rigo Marcel Ameloot Johan Hofkens 《Histochemistry and cell biology》2014,142(1):79-90
In this study, the effect of glycine receptor (GlyR) α3 alternative RNA splicing on the distribution of receptors in the membrane of human embryonic kidney 293 cells is investigated using optical super-resolution microscopy. Direct stochastic optical reconstruction microscopy is used to image both α3K and α3L splice variants individually and together using single- and dual-color imaging. Pair correlation analysis is used to extract quantitative measures from the resulting images. Autocorrelation analysis of the individually expressed variants reveals clustering of both variants, yet with differing properties. The cluster size is increased for α3L compared to α3K (mean radius 92 ± 4 and 56 ± 3 nm, respectively), yet an even bigger difference is found in the cluster density (9,870 ± 1,433 and 1,747 ± 200 μm?2, respectively). Furthermore, cross-correlation analysis revealed that upon co-expression, clusters colocalize on the same spatial scales as for individually expressed receptors (mean co-cluster radius 94 ± 6 nm). These results demonstrate that RNA splicing determines GlyR α3 membrane distribution, which has consequences for neuronal GlyR physiology and function. 相似文献