Nav3.1
Description: neuron navigator 3 Gene: Nav3 Synonyms: nav3.1
The third family of sodium channel isoforms is represented by a single member, Nav3.1 (originally known as NaN), which is less than 50% identical to any of the type 1 or type 2 channels. And type 2 and 3 channels differ greatly from the type 1 family, suggesting that these channels have completely different roles in vivo, although any indication about their significance awaits functional expression. Goldin, 1999, [899]
Gene
Transcript
Acc No | Sequence | Length | Source | |
---|---|---|---|---|
NM_001191782 | n/A | n/A | NCBI | |
NM_001081035 | n/A | n/A | NCBI | |
NM_014903 | n/A | n/A | NCBI |
Ontology
Accession | Name | Definition | Evidence | |||||||
---|---|---|---|---|---|---|---|---|---|---|
GO:0005634 | nucleus | A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent. | IEA | |||||||
GO:0005635 | nuclear envelope | The double lipid bilayer enclosing the nucleus and separating its contents from the rest of the cytoplasm; includes the intermembrane space, a gap of width 20-40 nm (also called the perinuclear space). | IEA |
Interaction
Nav3.1 is predicted to be resistant to nanomolar concentrations of TTX based on the presence of a serine rather than an aromatic residue at the TTX resistant site in domain I. Goldin [881]
Protein
Structure
The sequence of this channel is more similar to the type 1 than the type 2 family in the S4 segments and the domain III-IV linker. The number of positive charges in the S4 regions of domains I and IV are comparable to those present in type 1 channels, and the number in domains II and III are intermediate between types 1 and 2. The sequence in the domain III-IV linker includes the residues that are critical for normal inactivation. [881]
Nav3.1 is down-regulated after axotomy. Dib-Hajj [899].
The Nav3.1 channel is expressed in small fibers (sensory neurons) of the DRG and trigeminal ganglion, and the level of expression is down-regulated after axotomy. The channel has not been expressed in an exogenous system yet (1999). Goldin [881]
The complex Na current profile in DRG neurons influences their excitability [862], [900], [901], [902] and may contribute to ectopic or spontaneous firing in these cells after injury to their axons [903], [899], [861].
Changes in the Na current profile may contribute to neuropathic and inflammation-evoked pain. Dib-Hajj [899]
Kinetics
Model
References
Goldin AL
Diversity of mammalian voltage-gated sodium channels.
Ann. N. Y. Acad. Sci.,
1999
Apr
30
, 868 (38-50).
Dib-Hajj SD
et al.
NaN, a novel voltage-gated Na channel, is expressed preferentially in peripheral sensory neurons and down-regulated after axotomy.
Proc. Natl. Acad. Sci. U.S.A.,
1998
Jul
21
, 95 (8963-8).
Elliott AA
et al.
Characterization of TTX-sensitive and TTX-resistant sodium currents in small cells from adult rat dorsal root ganglia.
J. Physiol. (Lond.),
1993
Apr
, 463 (39-56).
Honmou O
et al.
Delayed depolarization and slow sodium currents in cutaneous afferents.
J. Neurophysiol.,
1994
May
, 71 (1627-37).
Jeftinija S
The role of tetrodotoxin-resistant sodium channels of small primary afferent fibers.
Brain Res.,
1994
Mar
7
, 639 (125-34).
Schild JH
et al.
A- and C-type rat nodose sensory neurons: model interpretations of dynamic discharge characteristics.
J. Neurophysiol.,
1994
Jun
, 71 (2338-58).
Rizzo MA
et al.
Mechanisms of paresthesiae, dysesthesiae, and hyperesthesiae: role of Na+ channel heterogeneity.
Eur. Neurol.,
1996
, 36 (3-12).
Cummins TR
et al.
Downregulation of tetrodotoxin-resistant sodium currents and upregulation of a rapidly repriming tetrodotoxin-sensitive sodium current in small spinal sensory neurons after nerve injury.
J. Neurosci.,
1997
May
15
, 17 (3503-14).
Credits
To cite this page: [Contributors] Channelpedia https://channelpedia.epfl.ch/ionchannels/133/ , accessed on [date]