Plasma membrane anion channels are thought to play important roles in osmoregulation and signal transduction in higher plant cells. Knowledge of their pharmacology and regulation is of importance to unravel their physiological functions. In this study, we explore the pharmacological properties and the nucleotide regulation of the voltage-dependent anion channel of Arabidopsis hypocotyls. The pharmacological profile of this channel is characterized by a low sensitivity to most anion channel blockers. It is inhibited by niflumic acid with an IC50 of 80 microM, but poorly sensitive to IAA-94 and NPPB and insensitive to 9-AC and DIDS. Nucleotides alter the amplitude, the kinetics and the voltage-dependence of the channel. The main effect of nucleotides is a shift of the voltage-dependent gate of the channel toward depolarized potentials leading to a strong reduction of the current amplitude. This regulation does not require ATP hydrolysis as nonhydrolyzable ATP analogues-AMPPNP and ATP gamma S-also regulate the anion current. This suggests that a nucleotide binding site is involved in the regulation. The study of the properties of this putative nucleotide binding site reveals that (i) ATP regulates the channel with an EC50 of 0.7 mM, (ii) adenyl nucleotides modulate the channel with the following order of effectiveness: ATP > ADP > > AMP, and (iii) thiophosphate nucleotide analogues are the most potent agonists with EC50 in the range of 80 microM. The hypothesis that this regulation may couple the electrical properties of the membrane with the metabolic status of the cell is discussed.
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Sci Rep
January 2025
Emergency department, The Fourth Hospital of Hebei Medical University, Shijiazhuang, 050011, Hebei, China.
Esophageal squamous cell carcinoma (ESCC) is one of the most common digestive malignancies. Our previous studies revealed necroptosis-related lncRNA ENSG00000253385.1 was an independent prognostic factor for ESCC.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Basis Dis
January 2025
Department of Cardiology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230001, China. Electronic address:
Cardiac arrest (CA) is a critical medical emergency that can occur in both patients with preexisting conditions and otherwise healthy individuals. Despite successful resuscitation through cardiopulmonary resuscitation (CPR), many survivors are at significant risk of developing post-cardiac arrest syndrome (PCAS), a complex systemic response to CA that includes brain injury as a major component. Phosphoenolpyruvate carboxykinase 1 (PCK1), the first rate-limiting enzyme in gluconeogenesis, has been implicated in various diseases.
View Article and Find Full Text PDFActa Physiol (Oxf)
February 2025
Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology, Rheumatology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Aim: Members of the claudin protein family are the major constituents of tight junction strands and determine the permeability properties of the paracellular pathway. In the kidney, each nephron segment expresses a distinct subset of claudins that form either barriers against paracellular solute transport or charge- and size-selective paracellular channels. It was the aim of the present study to determine and compare the permeation properties of these renal paracellular ion channel-forming claudins.
View Article and Find Full Text PDFNeural Regen Res
January 2025
Department of Human Anatomy and Neurobiology, School of Basic Medical Science, Central South University, Changsha, Hunan Province, China.
Ischemia-reperfusion injury is a common pathophysiological mechanism in retinal degeneration. PANoptosis is a newly defined integral form of regulated cell death that combines the key features of pyroptosis, apoptosis, and necroptosis. Oligomerization of mitochondrial voltage-dependent anion channel 1 is an important pathological event in regulating cell death in retinal ischemia-reperfusion injury.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Research Center for Membrane and Film Technology, Department of Chemical Science and Engineering, Kobe University, Kobe, 6500034, Japan.
Membrane technology holds significant potential for the recovery of acids and alkalis from industrial wastewater systems, with ion exchange membranes (IEMs) playing a crucial role in these applications. However, conventional IEMs are limited to separating only monovalent cations or anions, presenting a significant challenge in achieving concomitant H⁺/OH⁻ permselectivity for simultaneous acid and alkali recovery. To address this issue, the charged microporous polymer framework membranes are developed, featuring rigid Tröger's Base network chains constructed through a facile sol-gel process.
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