The York Research Database

TY - JOUR

T1 - Na+ Channel ß Subunits

T2 - Overachievers of the Ion Channel Family

AU - Brackenbury, William J

AU - Isom, Lori L

N1 - Copyright: © 2011 Brackenbury and Isom. This is an open-access article subject to a non-exclusive license between the authors and Frontiers Media SA, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and other Frontiers conditions are complied with.

PY - 2011/9/28

Y1 - 2011/9/28

N2 - Voltage-gated Na(+) channels (VGSCs) in mammals contain a pore-forming a subunit and one or more ß subunits. There are five mammalian ß subunits in total: ß1, ß1B, ß2, ß3, and ß4, encoded by four genes: SCN1B-SCN4B. With the exception of the SCN1B splice variant, ß1B, the ß subunits are type I topology transmembrane proteins. In contrast, ß1B lacks a transmembrane domain and is a secreted protein. A growing body of work shows that VGSC ß subunits are multifunctional. While they do not form the ion channel pore, ß subunits alter gating, voltage-dependence, and kinetics of VGSCa subunits and thus regulate cellular excitability in vivo. In addition to their roles in channel modulation, ß subunits are members of the immunoglobulin superfamily of cell adhesion molecules and regulate cell adhesion and migration. ß subunits are also substrates for sequential proteolytic cleavage by secretases. An example of the multifunctional nature of ß subunits is ß1, encoded by SCN1B, that plays a critical role in neuronal migration and pathfinding during brain development, and whose function is dependent on Na(+) current and ¿-secretase activity. Functional deletion of SCN1B results in Dravet Syndrome, a severe and intractable pediatric epileptic encephalopathy. ß subunits are emerging as key players in a wide variety of physiopathologies, including epilepsy, cardiac arrhythmia, multiple sclerosis, Huntington's disease, neuropsychiatric disorders, neuropathic and inflammatory pain, and cancer. ß subunits mediate multiple signaling pathways on different timescales, regulating electrical excitability, adhesion, migration, pathfinding, and transcription. Importantly, some ß subunit functions may operate independently of a subunits. Thus, ß subunits perform critical roles during development and disease. As such, they may prove useful in disease diagnosis and therapy.

AB - Voltage-gated Na(+) channels (VGSCs) in mammals contain a pore-forming a subunit and one or more ß subunits. There are five mammalian ß subunits in total: ß1, ß1B, ß2, ß3, and ß4, encoded by four genes: SCN1B-SCN4B. With the exception of the SCN1B splice variant, ß1B, the ß subunits are type I topology transmembrane proteins. In contrast, ß1B lacks a transmembrane domain and is a secreted protein. A growing body of work shows that VGSC ß subunits are multifunctional. While they do not form the ion channel pore, ß subunits alter gating, voltage-dependence, and kinetics of VGSCa subunits and thus regulate cellular excitability in vivo. In addition to their roles in channel modulation, ß subunits are members of the immunoglobulin superfamily of cell adhesion molecules and regulate cell adhesion and migration. ß subunits are also substrates for sequential proteolytic cleavage by secretases. An example of the multifunctional nature of ß subunits is ß1, encoded by SCN1B, that plays a critical role in neuronal migration and pathfinding during brain development, and whose function is dependent on Na(+) current and ¿-secretase activity. Functional deletion of SCN1B results in Dravet Syndrome, a severe and intractable pediatric epileptic encephalopathy. ß subunits are emerging as key players in a wide variety of physiopathologies, including epilepsy, cardiac arrhythmia, multiple sclerosis, Huntington's disease, neuropsychiatric disorders, neuropathic and inflammatory pain, and cancer. ß subunits mediate multiple signaling pathways on different timescales, regulating electrical excitability, adhesion, migration, pathfinding, and transcription. Importantly, some ß subunit functions may operate independently of a subunits. Thus, ß subunits perform critical roles during development and disease. As such, they may prove useful in disease diagnosis and therapy.

UR - http://www.scopus.com/inward/record.url?scp=84857211318&partnerID=8YFLogxK

U2 - 10.3389/fphar.2011.00053

DO - 10.3389/fphar.2011.00053

M3 - Literature review

C2 - 22007171

VL - 2

JO - Frontiers in Pharmacology

JF - Frontiers in Pharmacology

M1 - 53

ER -