SCN11A
Description
The SCN11A (sodium voltage-gated channel alpha subunit 11) is a protein-coding gene located on chromosome 3.
SCN11A, also known as Nav1.9, is a voltage-gated sodium channel protein that is encoded by the SCN11A gene on chromosome 3 in humans. Similar to Nav1.7 and Nav1.8, Nav1.9 is involved in pain perception. This channel is primarily expressed in small-diameter nociceptors of the dorsal root ganglion and trigeminal ganglion neurons, but is also found in intrinsic myenteric neurons. Voltage-gated sodium channels are essential membrane protein complexes that contribute to the rising phase of the action potential in most excitable cells. Alpha subunits, such as SCN11A, regulate voltage-dependent gating and conductance, while auxiliary beta subunits influence the channel's kinetic properties and facilitate the complex's membrane localization. Disruptions in the expression patterns or mutations of alpha subunits can lead to various disorders. Each alpha subunit comprises 4 domains connected by 3 intracellular loops, each domain consisting of 6 transmembrane segments and intra- and extracellular linkers. The 4th transmembrane segment of each domain acts as the voltage-sensing region of the channel. Upon cell depolarization, voltage-gated sodium channels undergo inactivation through a conformational change where the 4th segments in each domain move into the pore region in response to the highly positive voltage present at the peak of the action potential. This effectively blocks the Na+ pore, preventing further Na+ influx and subsequent depolarization.
SCN11A, also known as Nav1.9, is a voltage-gated sodium channel protein that mediates the movement of sodium ions across cell membranes. This protein undergoes conformational changes in response to voltage differences, forming a sodium-selective channel that allows sodium ions to pass along their electrochemical gradient. SCN11A plays a crucial role in membrane depolarization during action potentials in nociceptors, which are specialized sensory neurons that transmit pain signals from the periphery to the central nervous system. Additionally, SCN11A is involved in rapid BDNF-evoked neuronal depolarization.
SCN11A is also known as FEPS3, HSAN7, NAV1.9, NaN, PN5, SCN12A, SNS-2.
Associated Diseases
- Paroxysmal extreme pain disorder
- Neuropathy, hereditary sensory and autonomic, type VII
- Episodic pain syndrome, familial, 3
- Primary erythromelalgia
