A5062754043- Ion Channels and Receptors
- Neurobiology and Insect Physiology Research
- Phytochemicals and Antioxidant Activities
- Ion channel regulation and function
- Neuroscience and Neural Engineering
- Photoreceptor and optogenetics research
- Postharvest Quality and Shelf Life Management
- Biochemical Analysis and Sensing Techniques
- Respiratory and Cough-Related Research
- Pancreatic function and diabetes
- Insect Pest Control Strategies
- Microfluidic and Capillary Electrophoresis Applications
- Cardiac electrophysiology and arrhythmias
- Advanced biosensing and bioanalysis techniques
- Photochromic and Fluorescence Chemistry
- Magnesium in Health and Disease
- Advanced Memory and Neural Computing
- Cancer, Hypoxia, and Metabolism
- Plant Stress Responses and Tolerance
- Calcium signaling and nucleotide metabolism
- Neuroscience and Neuropharmacology Research
- Connexins and lens biology
- Conducting polymers and applications
- Aluminum Alloys Composites Properties
- Molecular Communication and Nanonetworks
BioTechMed-Graz
2019-2024
Medical University of Graz
2017-2024
Johannes Kepler University of Linz
2009-2020
Czech Academy of Sciences, Institute of Biophysics
2012-2013
Albany Medical Center Hospital
2013
University at Albany, State University of New York
2013
Albany State University
2013
Eastern Virginia Medical School
2013
Tulane University
2013
Institute of Biophysics
2009
STIM1 and ORAI1 (also termed CRACM1) are essential components of the classical calcium release-activated current; however, mechanism transmission information to calcium/ORAI1 channel is as yet unknown. Here we demonstrate by Förster resonance energy transfer microscopy a dynamic coupling that culminates in activation Ca2+ entry. imaging living cells provided insight into time dependence crucial events this signaling pathway comprising store depletion, multimerization, STIM1-ORAI1...
In immune cells, generation of sustained Ca(2+) levels is mediated by the release-activated (CRAC) current. Molecular key players in this process comprise stromal interaction molecule 1 (STIM1) that functions as a sensor endoplasmic reticulum and ORAI1 located plasma membrane. Depletion stores leads to STIM1 multimerization into discrete puncta, which co-cluster with couple activate channels. The cytosolic C terminus sufficient currents independent store depletion. Here we identified an...
Orai1 calcium channels in the plasma membrane are activated by stromal interaction molecule-1 (STIM1), an endoplasmic reticulum sensor, to mediate store-operated entry (SOCE). The cytosolic region of STIM1 contains a long putative coiled-coil (CC)1 segment and shorter CC2 CC3 domains. Here we present solution nuclear magnetic resonance structures trypsin-resistant CC1–CC2 fragment apo Orai1-bound states. Each subunit forms U-shaped structure that homodimerizes through antiparallel...
STIM1 and Orai1 have been reported to interact upon store depletion culminating in Ca(2+) release-activated current activation. Recently, the essential region has identified within C terminus that includes second coiled-coil domain C-terminally extended by approximately 50 amino acids exhibits a strong binding terminus. Based on homology Orai family, an analogous scenario might be assumed for Orai2 as well Orai3 channels both are activated similar STIM1-dependent manner. A combined approach...
Stromal interaction molecules (STIM)s function as endoplasmic reticulum calcium (Ca 2+ ) sensors that differentially regulate plasma membrane Ca release activated channels in various cells. To probe the structural basis for functional differences between STIM1 and STIM2 we engineered a series of EF-hand sterile α motif (SAM) domain (EF-SAM) chimeras, demonstrating -binding SAM are major contributors to autoinhibition oligomerization each respective isoform. Our nuclear magnetic resonance...
As the molecular composition of calcium-release activated calcium (CRAC) channels has been unknown for two decades, elucidation selective inhibitors considerably hampered. By identification key components CRAC channels, STIM1 and Orai1 have emerged as promising targets blockers. The aim this study was to thoroughly characterize effects channel blockers on currents derived from STIM1/Orai heterologoulsy expressed in HEK293 cells. novel compounds GSK-7975A GSK-5503A were tested mediated or...
Through largely unknown mechanisms, Ca(2+) signaling plays important roles in vascular smooth muscle cell (VSMC) remodeling. Orai1-encoded store-operated entry has recently emerged as an player VSMC However, the role of exclusively mammalian Orai3 protein native pathways, its upregulation during remodeling, and contribution to neointima formation remain unknown.The goal this study was determine agonist-evoked pathway contributed by Orai3; potential after balloon injury rat carotid...
Optical control of the electrophysiology single cells can be a powerful tool for biomedical research and technology. Here, we report organic electrolytic photocapacitors (OEPCs), devices that function as extracellular capacitive electrodes stimulating cells. OEPCs consist transparent conductor layers covered with donor-acceptor bilayer photoconductors. This device produces an open-circuit voltage in physiological solution 330 mV upon illumination using light tissue transparency window 630 to...
Cholesterol suppresses the activity of a channel needed to refill intracellular calcium stores.
Stim1 in the endoplasmic reticulum and three Orai (also termed CRACM) channels plasma-membrane are main components of native Ca2+ release-activated channels. A pharmacological hallmark these is their distinct sensitivity to 2-aminoethoxydiphenyl borate (2-APB). Here we report that Orai3 currents can be robustly stimulated by 75 μm 2-APB independent Stim1, whereas at similar concentrations inhibited store-operated Orai1 currents. did not only promote through but also dramatically altered ion...
STIM1 and ORAI1, the two limiting components in Ca(2+) release-activated (CRAC) signaling cascade, have been reported to interact upon store depletion, culminating CRAC current activation. We recently identified a modulatory domain between amino acids 474 485 cytosolic part of that comprises 7 negatively charged residues. A C-terminal fragment lacking this exhibits enhanced interaction with ORAI1 2-3-fold higher ORAI1/CRAC densities. Here we focused on role (CMD) fast inactivation channels,...
The Ca(2+)-selective TRPV6 as well the L-type Ca(2+) channel are regulated by Ca(2+)-binding protein calmodulin (CaM). Here, we investigated interaction of CaM with rat (r)TRPV6 in response to alterations intracellular Ca(2+), employing Ca(2+)-imaging and patch-clamp techniques. Additionally, confocal Förster resonance energy transfer (FRET) microscopy on living cells was utilized a key method visualize vivo protein-protein interactions essential for regulation rTRPV6 activity. effects...
Characterization of disease-associated Orai1 mutants reveals the multistep gating mechanism for CRAC channel.
Abstract The family of stromal interaction molecules (STIM) includes two widely expressed single‐pass endoplasmic reticulum (ER) transmembrane proteins and additional splice variants that act as precise ER‐luminal Ca 2+ sensors. STIM mainly function one the essential components so‐called release‐activated (CRAC) channel. second CRAC channel component is constituted by pore‐forming Orai in plasma membrane. physically interact with each other to enable opening, which a critical prerequisite...
Magnesium (Mg)-based implants are promising candidates for orthopedic interventions, because of their biocompatibility, good mechanical features, and ability to degrade completely in the body, eliminating need an additional removal surgery. In present study, we synthesized investigated two Mg-based materials, ultrahigh-purity ZX00 (Mg-Zn-Ca; <0.5 wt% Zn Ca, wt%; Fe-content <1 ppm) Mg (XHP-Mg, >99.999 Mg; ppm), vitro vivo juvenile healthy rats clarify effect alloying elements Ca on...
Abstract Recent advances in light‐responsive materials enabled the development of devices that can wirelessly activate tissue with light. Here it is shown solution‐processed organic heterojunctions stimulate activity primary neurons at low intensities light via photochemical reactions. The p‐type semiconducting polymer PDCBT and n‐type small molecule ITIC (a non‐fullerene acceptor) are coated on glass supports, forming a p – n junction high photosensitivity. Patch clamp measurements show...
Members of the CorA-Mrs2-Alr1 superfamily Mg(2+) transporters are ubiquitous among pro- and eukaryotes. The crystal structure a bacterial CorA protein has recently been solved, but mode ion transport this family remained obscure. Using single channel patch clamping we unequivocally show here that mitochondrial Mrs2 forms Mg(2+)-selective high conductance (155 pS). It an open probability approximately 60% in absence at matrix site, which decreases to 20% its presence. With lower ( 45 pS) is...
Successful formation of electronic interfaces between living cells and semiconductors hinges on being able to obtain an extremely close high surface-area contact, which preserves both cell viability semiconductor performance. To accomplish this, we introduce organic assemblies consisting a hierarchical arrangement nanocrystals. These are synthesised via colloidal chemical route that transforms the nontoxic commercial pigment quinacridone into various biomimetic three-dimensional arrangements...