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排序方式: 共有3203条查询结果,搜索用时 15 毫秒
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Karsten Schnatbaum Victor Solis‐Mezarino Daniil Pokrovsky Frederike Schfer Dennis Nagl Lars Hornberger Johannes Zerweck Tobias Knaute Julia Avramova‐Nehmer Mike Schutkowski Veit Hornung Holger Wenschuh Moritz Carl Vlker‐Albert Axel Imhof Ulf Reimer 《Proteomics》2020,20(10)
Targeted proteomics depends on the availability of stable isotope labeled (SIL) peptide standards, which for absolute protein quantification need to be absolutely quantified. In the present study, three new approaches for absolute quantification of SIL peptides are developed. All approaches rely on a quantification tag (Qtag) with a specific UV absorption. The Qtag is attached to the peptide during synthesis and is removed by tryptic digestion under standard proteomics workflow conditions. While one quantification method (method A) is designed to allow the fast and economic production of absolutely quantified SIL peptides, two other methods (methods B and C) are developed to enable the straightforward re‐quantification of SIL peptides after reconstitution to control and monitor known problems related to peptide solubility, precipitation, and adhesion to vials. All methods yield consistent results when compared to each other and when compared to quantification by amino acid analysis. The precise quantitation methods are used to characterize the in vivo specificity of the H3 specific histone methyltransferase EZH2. 相似文献
75.
Leon Green Jan Niemax Jens‐Peter Herrmann Axel Temming Charlotta Kvarnemo 《Ecology and evolution》2020,10(18):9981-9999
During male–male competition, evolution can favor alternative reproductive tactics. This often results in a dominant morph that holds a resource, such as a nest for egg laying, which competes with a smaller sneaker morph that reproduces by stealing fertilizations. The salinity environment can influence male growth rates, for example, via osmoregulatory costs, which in turn may influence the use of sneaker tactics for small males competing for mating opportunities. Salinity can also affect sperm directly; however, little is known of how salinity influences sneaker tactics through sperm performance. We sampled males of the invasive round goby (Neogobius melanostomus) from two environments, a freshwater river and a brackish estuary. This fish has two male morphs: nest‐holding dark males and non‐nest‐holding light males. We examined the role of water salinity of 0, 8, and 16 on sperm performance and found that for estuarine males, a salinity of 0 reduced sperm velocity compared to a salinity of 8 and 16. Riverine males had low velocity in all salinities. Sperm viability also decreased by over 30% in 0 salinity, compared to 8 and 16, for fish from both environments. Gobies produce ejaculate contents in specialized glands that could in theory shield sperm in an adverse environment. However, gland contents did not improve sperm performance in our tests. Body mass and age estimates indicate that riverine males invested more in somatic growth compared to estuarine males. Estuarine light morph males had a high enough gonadosomatic index to indicate sneaker tactics. We propose that when sperm performance is low, such as for the riverine males, sneaker tactics are ineffective and will be selected against or phenotypically suppressed. Instead, we interpret the increased investment in somatic growth found in riverine males as a life‐history decision that is advantageous when defending a nest in the next reproductive season. 相似文献
76.
Manfred Schartl Susanne Kneitz Jenny Ormanns Cornelia Schmidt Jennifer L. Anderson Angel Amores Julian Catchen Catherine Wilson Dietmar Geiger Kang Du Mateo Garcia-Olazábal Sudha Sudaram Christoph Winkler Rainer Hedrich Wesley C. Warren Ronald Walter Axel Meyer John H. Postlethwait 《Current biology : CB》2021,31(5):911-922.e4
77.
Ulrich Schulte Michael Veith Valentin Mingo Corrado Modica Axel Hochkirch 《Biological invasions》2013,15(12):2639-2649
Biological invasions represent ideal systems for the study of evolutionary processes associated with colonization events. It has been hypothesized that the genetic diversity is generally decreasing from the centre of the range to the margins due to multiple founder events. Invasive populations offer the opportunity to test this hypothesis at a fine spatial and temporal scale. We analysed the genetic structure of a large expanding non-native population of the Common Wall Lizard (Podarcis muralis) in Passau (Germany) using thirteen microsatellite loci. We analyzed the genetic structure and levels of admixture across a transect reflecting the expansion process and tested for a loss of genetic diversity and an increase of genetic differentiation from the centre to the invasion front. Our results demonstrate that significant genetic population structure can emerge rapidly at a small spatial scale. We found a trend for an increase in genetic differentiation and a decrease in genetic diversity from the invasion centre to the expanding range margin, suggesting that genetic drift is the major factor causing this pattern. The correlation between genetic diversity and average genetic differentiation was significant among sites. We hypothesize that the territoriality of P. muralis generates sufficient rates of noncontiguous and stratified dispersal from longer established sites to maintain significant genetic diversity at the invasion front. Simultaneously, territoriality might restrict the colonization success of migrants at established sites, so that in combination with founder events a strong differentiation arises. 相似文献
78.
Oncogene-induced senescence (OIS) is characterised by a stable cell cycle arrest triggered by activated oncogenes and tumour suppressors. Whilst the in vivo relevance of OIS as a mode of tumour suppression is now beyond doubt many key questions with regard to the underlying mechanisms remain unanswered. To address these questions, we first review current knowledge of the essential players and pathways in OIS focussing our discussions mainly on murine cell systems and the paradigm of Ras-induced senescence. We then update experimental evidence for the involvement of the Runx genes that have recently emerged as important mediators of OIS. Of particular interest is the observation that Runx2 disruption renders primary murine embryonic fibroblasts (MEFs) refractory to Ras-induced senescence despite induction of a cascade of growth inhibitors and senescence markers. We suggest that Runx acts downstream of p53 in the "execution phase" of senescence specifically through deregulation of cyclin gene expression. We speculate how this might operate and consider the implications of these findings for the emerging role of the Runx family as tumour suppressors. 相似文献
79.
Carmen Methner Guido Buonincontri Chou-Hui Hu Ana Vujic Axel Kretschmer Stephen Sawiak Adrian Carpenter Johannes-Peter Stasch Thomas Krieg 《PloS one》2013,8(12)
Aim
Stimulation of the nitric oxide (NO) – soluble guanylate (sGC) - protein kinase G (PKG) pathway confers protection against acute ischaemia/reperfusion injury, but more chronic effects in reducing post-myocardial infarction (MI) heart failure are less defined. The aim of this study was to not only determine whether the sGC stimulator riociguat reduces infarct size but also whether it protects against the development of post-MI heart failure.Methods and Results
Mice were subjected to 30 min ischaemia via ligation of the left main coronary artery to induce MI and either placebo or riociguat (1.2 µmol/l) were given as a bolus 5 min before and 5 min after onset of reperfusion. After 24 hours, both, late gadolinium-enhanced magnetic resonance imaging (LGE-MRI) and 18F-FDG-positron emission tomography (PET) were performed to determine infarct size. In the riociguat-treated mice, the resulting infarct size was smaller (8.5±2.5% of total LV mass vs. 21.8%±1.7%. in controls, p = 0.005) and LV systolic function analysed by MRI was better preserved (60.1%±3.4% of preischaemic vs. 44.2%±3.1% in controls, p = 0.005). After 28 days, LV systolic function by echocardiography treated group was still better preserved (63.5%±3.2% vs. 48.2%±2.2% in control, p = 0.004).Conclusion
Taken together, mice treated acutely at the onset of reperfusion with the sGC stimulator riociguat have smaller infarct size and better long-term preservation of LV systolic function. These findings suggest that sGC stimulation during reperfusion therapy may be a powerful therapeutic treatment strategy for preventing post-MI heart failure. 相似文献80.
Christina R?hr Martin Kerick Axel Fischer Alexander Kühn Karl Kashofer Bernd Timmermann Andriani Daskalaki Thomas Meinel Dmitriy Drichel Stefan T. B?rno Anja Nowka Sylvia Krobitsch Alice C. McHardy Christina Kratsch Tim Becker Andrea Wunderlich Christian Barmeyer Christian Viertler Kurt Zatloukal Christoph Wierling Hans Lehrach Michal R. Schweiger 《PloS one》2013,8(7)
MiRNAs are discussed as diagnostic and therapeutic molecules. However, effective miRNA drug treatments with miRNAs are, so far, hampered by the complexity of the miRNA networks. To identify potential miRNA drugs in colorectal cancer, we profiled miRNA and mRNA expression in matching normal, tumor and metastasis tissues of eight patients by Illumina sequencing. We validated six miRNAs in a large tissue screen containing 16 additional tumor entities and identified miRNA-1, miRNA-129, miRNA-497 and miRNA-215 as constantly de-regulated within the majority of cancers. Of these, we investigated miRNA-1 as representative in a systems-biology simulation of cellular cancer models implemented in PyBioS and assessed the effects of depletion as well as overexpression in terms of miRNA-1 as a potential treatment option. In this system, miRNA-1 treatment reverted the disease phenotype with different effectiveness among the patients. Scoring the gene expression changes obtained through mRNA-Seq from the same patients we show that the combination of deep sequencing and systems biological modeling can help to identify patient-specific responses to miRNA treatments. We present this data as guideline for future pre-clinical assessments of new and personalized therapeutic options. 相似文献