Na+ channel protein type 2 subunit alpha; Na+ channel protein type II subunit alpha; voltage-gated Na+ channel subunit alpha Nav1.2; Na+ channel protein, brain II subunit alpha; HBSC II (SCN2A, NAC2, SCN2A1, SCN2A2)

Function

• mediates voltage-dependent Na+ permeability of excitable membranes
• assumes opened or closed conformation in response to voltage difference across the membrane,
• forms a Na+-selective channel through which Na+ ions may pass in accordance with their electrochemical gradient
• may be ubiquitinated by NEDD4L; which would promote its endocytosis (putative)
• the Na+ channel consists of a large polypeptide & 2-3 smaller ones interacts with NEDD4L (putative)

Structure

• large polypeptide with 4 internal repeats, each with 5 hydrophobic segments (S1,S2,S3,S5,S6) & one positively charged segment (S4)
• segments S4 are probably the voltage-sensors & are characterized by a series of positively charged amino acids at every third position
• belongs to the Na+ channel family
• contains 1 IQ domain

Compartment

membrane

Alternative splicing

named isoforms=2

Pathology

• defects in SCN2A are a cause of
  • generalized epilepsy with febrile seizures plus (GEFS+)
  • benign familial infantile convulsions type 3

More general terms

• voltage-dependent Na+ channel protein alpha subunit
• glycoprotein

Additional terms

• voltage-dependent Na+ channel

Database

• UniProt: http://www.uniprot.org/uniprot/Q99250.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=6326
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:6326
• OMIM: https://mirror.omim.org/entry/182390
• OMIM: https://mirror.omim.org/entry/604233
• OMIM: https://mirror.omim.org/entry/607745