The most common oncogenic mutations in multiple myeloma (MM) affect N- and K-RAS leading to constitutive activation of RAS-dependent signaling. Signal transduction via RAS, Raf and MAPK has been well described as a canonical pathway. In accordance with this assumption, we showed that the activity of the MEK/ERK module is strictly dependent on pan-Raf activity. However, inhibition of MEK/ERK has no or only minor effects on MM cell survival, whereas oncogenic Ras and pan-Raf critically contribute to survival of multiple myeloma cells. Therefore, we aimed to learn more about Raf-dependent but MEK-independent signaling effectors.
Pan-Raf co-operates with PI3K-dependent signalling and critically contributes to myeloma cell survival independently of mutated RAS.
Cell line
View SamplesRationale: Monitoring and controlling cardiomyocyte activity with optogenetic tools offers exciting possibilities for fundamental and translational cardiovascular research. Genetically encoded voltage indicators may be particularly attractive for minimal invasive and repeated assessments of cardiac excitation from the cellular to the whole heart level. Objective: To test the hypothesis that cardiomyocyte-targeted voltage-sensitive fluorescence protein 2.3 (VSFP2.3) can be exploited as optogenetic tool for the monitoring of electrical activity in isolated cardiomyocytes and the whole heart as well as function and maturity in induced pluripotent stem cell (iPSC)-derived cardiomyocytes. Methods and Results: We first generated mice with cardiomyocyte-restricted expression of VSFP2.3 and demonstrated distinct sarcolemmal localization of VSFP2.3 without any signs for associated pathologies (assessed by echocardiography). Optically recorded VSFP2.3 signals correlated well with membrane voltage measured simultaneously by patch-clamping. The utility of VSFP2.3 for human action potential recordings was confirmed by simulation of immature and mature action potentials in murine VSFP2.3 cardiomyocytes. Optical cardiograms (OCGs) could be monitored in whole hearts ex vivo and minimally invasively in vivo via fiber optics at physiological heart rate (10 Hz) and under pacing-induced arrhythmia. Finally, we reprogrammed tail-tip fibroblasts from transgenic mice and used the VSFP2.3 sensor for benchmarking functional and structural maturation in iPSC-derived cardiomyocytes. Conclusions: We introduce a novel transgenic voltage-sensor model as a new method in cardiovascular research and provide proof-of-concept for its utility in optogenetic sensing of physiological and pathological excitation in mature and immature cardiomyocytes in vitro and in vivo. Overall design: Determination of transgene (VSFP2.3) cardiotoxicity
Sensing Cardiac Electrical Activity With a Cardiac Myocyte--Targeted Optogenetic Voltage Indicator.
No sample metadata fields
View SamplesBio-electrospray, the direct jet-based cell handling apporach, is able to handle a wide range of cells. Studies at the genomic, genetic, and the physiological level have shown that, post-treatment, cellular integrity is unperturbed and a high percentage (>70%, compared to control) of cells remain viable. Although, these results are impressive, it may be argued that cell based systems are oversimplistic. This study utilizing a well characterised multicellular model organism, the non-parasitic nematode Caenorhabditis elegans. Nematodes were subjected to bio-electrosprays to demonstrate that bio-electrosprays can be safely applied to nematodes.
Bio-electrospraying the nematode Caenorhabditis elegans: studying whole-genome transcriptional responses and key life cycle parameters.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Toxicogenomics of iron oxide nanoparticles in the nematode C. elegans.
Specimen part
View SamplesSuperparamagnetic Iron Oxide Nanoparticles (SPIONs) are currently being investigated for a range of biomedical applications. Their use have been related with different cytotoxic mechanisms including the generation of oxidative stress and the induction of metal detoxification pathways, among others. We have investigated the molecular mechanisms responsive to in-house fabricated citrate coated SPIONs (C-SPIONs) in the nematode C. elegans to compare in vivo findings with previous in vitro studies. C-SPIONs (500 g/ml) affected the transcriptional response of signal transduction cascades (i.e. TFG-beta), protein processing in the endoplasmic reticulum, and RNA transport, among other biological processes. They also triggered a lysosomal response, indicating a relevant biological role of this cellular compartment in the response to this nanoparticle treatment in C. elegans. Interestingly, other pathways frequently linked to nanotoxicity like oxidative stress or apoptosis were not identified as significantly affected in this genome-wide in vivo study despite the high dose of exposure.
Toxicogenomics of iron oxide nanoparticles in the nematode C. elegans.
Specimen part
View SamplesSuperparamagnetic Iron Oxide Nanoparticles (SPIONs) are currently being investigated for a range of biomedical applications. Their use have been related with different cytotoxic mechanisms including the generation of oxidative stress and the induction of metal detoxification pathways, among others. Different NP coatings are being explored, among them albumin which has been applied in some drugs delivery systems. We have investigated the molecular mechanisms responsive to in-house fabricated SPIONs coated with bovine serum albumin (BSA-SPIONs) in the nematode C. elegans to compare in vivo findings with previous in vitro studies. BSA-SPIONs (500 g/ml) affected the transcriptional response of glycan metabolic pathways related to innate immune response, xenobiotics degradation, and triggered a lysosomal response, indicating a relevant biological role of this cellular compartment in the response to this nanoparticle treatment in C. elegans. Remarkably, key biological functions such as apoptosis or protein processing were not affected with significance despite the high dose of exposure.
Toxicogenomics of iron oxide nanoparticles in the nematode C. elegans.
Specimen part
View SamplesBiopsies from uninvolved and from lesional skin of 13 patients with plaque-type psoriasis. Based on paired samples, 179 genes were more than 2-fold differentially expressed in lesional skin.
Increased expression of Wnt5a in psoriatic plaques.
Sex, Age
View SamplesRecent research has highlighted that the polyphenols Quercetin (Q) and Tannic acid (TA) are capable of extending the lifespan of C. elegans. To gain a deep understanding of the underlying molecular genetics, we analyzed the global transcriptional patterns of nematodes exposed to Quercetin or Tannic acid concentrations that are non-effective (in lifespan extension), lifespan extending or toxic.
Meta-Analysis of Global Transcriptomics Suggests that Conserved Genetic Pathways are Responsible for Quercetin and Tannic Acid Mediated Longevity in C. elegans.
Specimen part, Treatment
View SamplesLow concentrations of the dissolved leonardite humic acid HuminFeed (HF) prolonged the lifespan and enhanced the thermal stress resistance of the model organism Caenorhabditis elegans. Furthermore growth was impaired and reproduction delayed, effects which have also been identified in other polyphenolic monomers, including tannic acid, rosmarinic acid, and caffeic acid. Moreover, a chemical modification of HF (HF-HQ), which increases its phenolic/quinonoid moieties, magnified the biological impact on C. elegans. To gain a deep insight into the molecular basis of these effects, we performed global transcriptomics on young adult (3 d) and old adult (11 d) nematodes exposed to two concentrations of HF and young adults (3 d) exposed to two concentrations of HF-HQ.
The Nematode Caenorhabditis elegans, Stress and Aging: Identifying the Complex Interplay of Genetic Pathways Following the Treatment with Humic Substances.
Specimen part, Treatment
View SamplesOligomeric proanthocyanidins (OPCs) reduce triglycerides in the nematode C. elegans. Lipase was strongly inhibited in vitro accompanied by the reduction of total triglyceride storage capacity in vivo; Lipophilic staining was also attenuated in wild type worms and high-fat mutants exposed to OPCs. Apart from biochemical analyses, lipid metabolism was also genetically regulated, emphasizing the necessity to study underlying regulation mechanisms in intact animals. To gain a deeper insight into the potential gene targets of purified oligomeric proanthocyanidin trimer gallate (pOPC7), a binary microarray assay was carried out with wild type N2 populations continuously exposed to a bacterial diet with or without pOPC7.
Proanthocyanidin trimer gallate modulates lipid deposition and fatty acid desaturation in <i>Caenorhabditis elegans</i>.
Sex, Treatment
View Samples