voltage-dependent Ca+2 channel

Function

• voltage-sensitive Ca+2 channels (VSCC) mediate the entry of Ca+2 into excitable cells
• roles in a variety of Ca+2-dependent processes, including
  • muscle contraction
  • hormone or neurotransmitter release
  • gene expression
  • cell motility
  • cell division
  • cell death

Structure

• multisubunit complexes, consisting of alpha-1 (CACNA1), alpha-2-delta (CACNA2D), beta (CACNB) subunits in a 1:1:1 ratio
• alpha-2-delta transcribed from a single gene; unclear if protein is cleave into separate alpha-2 & delta subunits
• L-type Ca+2 channels also contain a gamma subunit
• the channel activity is directed by the pore-forming & voltage-sensitive alpha-1 subunit
• in many cases, the alpha-1 subunit is sufficient to generate voltage-sensitive Ca+2 channel activity
• the auxiliary subunits beta & alpha-2/delta linked by a disulfide bridge regulate channel activity

More general terms

• voltage-gated ion channel
• Ca+2 channel
• plasma membrane protein
• multisubunit protein

More specific terms

• cation channel sperm-associated protein 2 (Catsper2, CATSPER2)
• L-type Ca+2 channel, long duration or slowly inactivating Ca+2 channel or dihydropyridine receptor (R-type Ca+2 channel)
• N-type Ca+2 channel or neuronal-type Ca+2 channel
• NMDA receptor
• P-type Ca+2 channel or Purkinje cell Ca+2 channel
• T-type Ca+2 channel or transient current Ca+2 channel