Store-operated Ca2+ channels in the plasma membrane (PM) are activated by the depletion of Ca2+ from the endoplasmic reticulum (ER) and constitute a widespread and highly conserved Ca2+ influx pathway. After store emptying, the ER Ca2+ sensor STIM1 forms multimers, which then migrate to ER-PM junctions where they activate the Ca2+ release-activated Ca2+ channel Orai1. Movement of an intracellular protein to such specialized sites where it gates an ion channel is without precedence, but the fundamental question of how STIM1 migrates remains unresolved. Here, we show that trafficking of STIM1 to ER-PM junctions and subsequent Ca2+ release-activated Ca2+ channel activity is impaired following mitochondrial depolarization. We identify the dynamin-related mitochondrial protein mitofusin 2, mutations of which causes the inherited neurodegenerative disease Charcot-Marie-Tooth IIa in humans, as an important component of this mechanism. Our results reveal a molecular mechanism whereby a mitochondrial fusion protein regulates protein trafficking across the endoplasmic reticulum and reveals a homeostatic mechanism whereby mitochondrial depolarization can inhibit store-operated Ca2+ entry, thereby reducing cellular Ca2+ overload.
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http://dx.doi.org/10.1074/jbc.M110.174029 | DOI Listing |
Langmuir
January 2025
Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, ul. Berdychowo 4, PL 60-965 Poznan, Poland.
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View Article and Find Full Text PDFEnergy Fuels
January 2025
Geothermal Energy and Geofluids Group, Institute of Geophysics, Department of Earth and Planetary Sciences, ETH Zurich, Zurich 8092, Switzerland.
Carbon capture and storage (CCS) and CO-based geothermal energy are promising technologies for reducing CO emissions and mitigating climate change. Safe implementation of these technologies requires an understanding of how CO interacts with fluids and rocks at depth, particularly under elevated pressure and temperature. While CO-bearing aqueous solutions in geological reservoirs have been extensively studied, the chemical behavior of water-bearing supercritical CO remains largely overlooked by academics and practitioners alike.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Department of Biopharmacy, School of Pharmaceutical Sciences, Jilin University, Changchun, People's Republic of China.
Purpose: Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. Oxaliplatin (OXA) is currently the primary chemotherapeutic agent for CRC, but its efficacy is limited by the tumor microenvironment (TME). Here, we present a combined approach of chemotherapy and TME modulation for CRC treatment.
View Article and Find Full Text PDFThe hippocampus forms memories of our experiences by registering processed sensory information in coactive populations of excitatory principal cells or ensembles. Fast-spiking parvalbumin-expressing inhibitory neurons (PV INs) in the dentate gyrus (DG)-CA3/CA2 circuit contribute to memory encoding by exerting precise temporal control of excitatory principal cell activity through mossy fiber-dependent feed-forward inhibition. PV INs respond to input-specific information by coordinating changes in their intrinsic excitability, input-output synaptic-connectivity, synaptic-physiology and synaptic-plasticity, referred to here as experience-dependent PV IN plasticity, to influence hippocampal functions.
View Article and Find Full Text PDFDecades after their initial observation in prion-infected brain tissues, the identities of virus-like dense particles, varicose tubules, and oval bodies containing parallel bands and fibrils have remained elusive. Our recent work revealed that a phenotype of dilation of the endoplasmic reticulum (ER), most notable for the perinuclear space (PNS), contributes to spongiform degeneration. To assess the significance of this phenotype for the etiology of prion diseases, we explored whether it can be functionally linked to other neuropathological hallmarks observed in these diseases, as this would indicate it to be a central event.
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