Biophysical Characterization of the human Nav1.9 sodium channel in trigeminal ganglia and dorsal root ganglia neurons
Abstract
Abstract In human dorsal root ganglia (DRG), and trigeminal (TG) neurons, the various voltage-gated sodium channel (Nav) isoforms play critical roles in the firing of action potentials, which drive electrical impulses that encode somatosensations including, itch, and pain. The SCN11A gene encodes the tetrodotoxin (TTX)-resistant voltage-gated sodium channel Nav1.9, characterized by unique gating properties. Unlike other isoforms, the Nav1.9 channel activates and inactivates slowly and has a hyperpolarized voltage-dependence of activation and depolarized voltage-dependence of inactivation. This leads to a large window current that has been suggested to function as a regulator of the resting membrane potential of neurons. Mutations in Nav1.9 channels lead to congenital insensitivity to pain (gain-of-function) or familial episodic pain syndrome (loss-of-function) suggesting the channel is a critical mediator of pain. Despite its relevance in pain pathophysiology, most existing data relies on rodent models or heterologous expression systems, leaving the specific pharmacology and biophysical behavior of these channels in human primary neurons largely unknown. In this study, we pharmacologically isolated and characterized native Nav1.9 channel currents in human DRG and TG neurons to compare their biophysical profiles. Our findings reveal significant kinetic and voltage-dependent differences between the two populations. Specifically, Nav1.9 channels in TG neurons exhibit a…
Read the paper
Related studies
- Noninvasive and Point-of-Care Surface-Enhanced Raman Scattering (SERS)-Based Breathalyzer for Mass Screening of Coronavirus Disease 2019 (COVID-19) under 5 min
- De Novo Transcriptome Analysis and Detection of Antimicrobial Peptides of the American Cockroach Periplaneta americana (Linnaeus)
- Molecular Characterization and Expression Profiling of Tomato GRF Transcription Factor Family Genes in Response to Abiotic Stresses and Phytohormones
- Assembly of Tight Junction Strands: Claudin-10b and Claudin-3 Form Homo Tetrameric Building Blocks that Polymerise in a Channel-Independent Manner
- Update of the Pompe variant database for the prediction of clinical phenotypes: Novel disease‐associated variants, common sequence variants, and results from newborn screening
- Machine Learning-Based SERS Chemical Space for Two-Way Prediction of Structures and Spectra of Untrained Molecules
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.