Search results for "cellular"

A Thermodynamic Model of Monovalent Cation Homeostasis in the Yeast Saccharomyces cerevisiae

2016

Cationic and heavy metal toxicity is involved in a substantial number of diseases in mammals and crop plants. Therefore, the understanding of tightly regulated transporter activities, as well as conceiving the interplay of regulatory mechanisms, is of substantial interest. A generalized thermodynamic description is developed for the complex interplay of the plasma membrane ion transporters, membrane potential and the consumption of energy for maintaining and restoring specific intracellular cation concentrations. This concept is applied to the homeostasis of cation concentrations in the yeast cells of S. cerevisiae. The thermodynamic approach allows to model passive ion fluxes driven by the…

Eomes broadens the scope of CD8 T-cell memory by inhibiting apoptosis in cells of low affinity.

2020

The memory CD8 T-cell pool must select for clones that bind immunodominant epitopes with high affinity to efficiently counter reinfection. At the same time, it must retain a level of clonal diversity to allow recognition of pathogens with mutated epitopes. How the level of diversity within the memory pool is controlled is unclear, especially in the context of a selective drive for antigen affinity. We find that preservation of clones that bind the activating antigen with low affinity depends on expression of the transcription factor Eomes in the first days after antigen encounter. Eomes is induced at low activating signal strength and directly drives transcription of the prosurvival protein…

The role of spatial structure in the evolution of viral innate immunity evasion: A diffusion-reaction cellular automaton model

2020

Most viruses have evolved strategies for preventing interferon (IFN) secretion and evading innate immunity. Recent work has shown that viral shutdown of IFN secretion can be viewed as a social trait, since the ability of a given virus to evade IFN-mediated immunity depends on the phenotype of neighbor viruses. Following this idea, we investigate the role of spatial structure in the evolution of innate immunity evasion. For this, we model IFN signaling and viral spread using a spatially explicit approximation that combines a diffusion-reaction model and cellular automaton. Our results indicate that the benefits of preventing IFN secretion for a virus are strongly determined by spatial struct…

The EP300/TP53 pathway, a suppressor of the Hippo and canonical WNT pathways, is activated in human hearts with arrhythmogenic cardiomyopathy in the …

2021

Aim Arrhythmogenic cardiomyopathy (ACM) is a primary myocardial disease that typically manifests with cardiac arrhythmias, progressive heart failure and sudden cardiac death (SCD). ACM is mainly caused by mutations in genes encoding desmosome proteins. Desmosomes are cell-cell adhesion structures and hubs for mechanosensing and mechanotransduction. The objective was to identify the dysregulated molecular and biological pathways in human ACM in the absence of overt heart failure. Methods and results Transcriptomes in the right ventricular endomyocardial biopsy samples from three independent individuals carrying truncating mutations in the DSP gene and 5 control samples were analyzed by RNA-S…

Single nucleotide polymorphisms in A4GALT spur extra products of the human Gb3/CD77 synthase and underlie the P1PK blood group system.

2018

Contrary to the mainstream blood group systems, P1PK continues to puzzle and generate controversies over its molecular background. The P1PK system comprises three glycosphingolipid antigens: Pk, P1 and NOR, all synthesised by a glycosyltransferase called Gb3/CD77 synthase. The Pk antigen is present in most individuals, whereas P1 frequency is lesser and varies regionally, thus underlying two common phenotypes: P1, if the P1 antigen is present, and P2, when P1 is absent. Null and NOR phenotypes are extremely rare. To date, several single nucleotide polymorphisms (SNPs) have been proposed to predict the P1/P2 status, but it has not been clear how important they are in general and in relation …

Silencing of C3G increases cardiomyocyte survival inhibition and apoptosis via regulation of p-ERK1/2 and Bax.

2018

Experimental studies have shown that overexpression of Rap guanine nucleotide exchange factor 1 (C3G) plays pro-survival and anti-apoptotic roles through molecule phosphorylated extracellular signal-regulated kinase1/2 (p-ERK1/2) in cardiomyocytes. However, it is still unclear if silencing of C3G may increase cell survival inhibition and apoptosis in cardiomyocytes, and whether C3G silence induced injuries are reduced by the overexpression of C3G through regulation of p-ERK1/2 and pro-apoptotic molecule Bax. In this study, the rat-derived H9C2 cardiomyocytes were infected with C3G small hairpin RNA interference recombinant lentiviruses, which silenced the endogenous C3G expression in the ca…

2020

Physical exercise induces acute physiological changes leading to enhanced tissue cross-talk and a liberation of extracellular vesicles (EVs) into the circulation. EVs are cell-derived membranous entities which carry bioactive material, such as proteins and RNA species, and are important mediators of cell-cell-communication. Different types of physical exercise interventions trigger the release of diverse EV subpopulations, which are hypothesized to be involved in physiological adaptation processes leading to health benefits and longevity. Large EVs (“microvesicles” and “microparticles”) are studied frequently in the context of physical exercise using straight forward flow cytometry approach…

Comparative Proteomics Unveils LRRFIP1 as a New Player in the DAPK1 Interactome of Neurons Exposed to Oxygen and Glucose Deprivation

2020

Altres ajuts: The group has received funding from 'la Caixa Foundation' CI15-00009, from the European Institute of Innovation and Technology (EIT) PoC-2016-SPAIN-04, which receives support from the European Union's Horizon 2020 research and innovation program, and from the 'Fundación para la Innovación y la Prospectiva en Salud en España (FIPSE)' program 3594-18. Death-associated protein kinase 1 (DAPK1) is a pleiotropic hub of a number of networked distributed intracellular processes. Among them, DAPK1 is known to interact with the excitotoxicity driver NMDA receptor (NMDAR), and in sudden pathophysiological conditions of the brain, e.g., stroke, several lines of evidence link DAPK1 with t…

A conditional inducible JAK2V617F transgenic mouse model reveals myeloproliferative disease that is reversible upon switching off transgene expressio…

2019

Aberrant activation of the JAK/STAT pathway is thought to be the critical event in the pathogenesis of the chronic myeloproliferative neoplasms, polycythemia vera, essential thrombocythemia and primary myelofibrosis. The most frequent genetic alteration in these pathologies is the activating JAK2V617F mutation, and expression of the mutant gene in mouse models was shown to cause a phenotype resembling the human diseases. Given the body of genetic evidence, it has come as a sobering finding that JAK inhibitor therapy only modestly suppresses the JAK2V617F allele burden, despite showing clear benefits in terms of reducing splenomegaly and constitutional symptoms in patients. To gain a better …

Stimulation of natural killer cells with rhCD137 ligand enhances tumor-targeting antibody efficacy in gastric cancer

2018

Although many anticancer agents for gastric cancer have been developed, the prognosis for many patients remains poor. Recently, costimulatory immune molecules that reactivate antitumor immune responses by utilizing the host immune system have attracted attention as new therapeutic strategies. CD137 is a costimulatory molecule that reportedly potentiates the antitumor activity of tumor-targeting monoclonal antibodies (mAbs) by enhancing antibody-dependent cellular cytotoxicity. However, it remains unclear whether CD137 stimulates tumor-regulatory activity in gastric cancer. In this study, we investigated the antitumor effects of CD137 stimulation on gastric cancer cells administered tumor-ta…