Regulation of neuronal activity by Cav3-Kv4 channel signaling complexes.
Kv4 low voltage-activated A-type potassium channels are widely expressed in excitable cells, where they control action potential firing, dendritic activity and synaptic integration. Kv4 channels exist as a complex that includes K(+) channel-interacting proteins (KChIPs), which contain calcium-binding domains and therefore have the potential to confer calcium dependence on the Kv4 channel. We found that T-type calcium channels and Kv4 channels form a signaling complex in rat that efficiently couples calcium influx to KChIP3 to modulate Kv4 function. This interaction was critical for allowing Kv4 channels to function in the subthreshold membrane potential range to regulate neuronal firing properties. The widespread expression of these channels and accessory proteins indicates that the Cav3-Kv4 signaling complex is important for the function of a wide range of electrically excitable cells.
Department of Physiology & Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.
Dustin
D
Anderson
W Hamish
WH
Mehaffey
Mircea
M
Iftinca
Renata
R
Rehak
Jordan D T
JD
Engbers
Shahid
S
Hameed
Gerald W
GW
Zamponi
Ray W
RW
Turner
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D020747:Calcium Channels, T-Type / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D005110:Extracellular Space / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D051605:Kv Channel-Interacting Proteins / Q000378:metabolism; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D051672:Shal Potassium Channels / Q000378:metabolism*
D020747:Calcium Channels, T-Type; D051605:Kv Channel-Interacting Proteins; D051672:Shal Potassium Channels; D002118:Calcium