KV7.2 kanala: estruktura, erregulazioa eta kitzikagarritasun neuronalean duen ekintza

Abstract

Potassium channels are present in almost all cell membranes and perform important biological functions, including electrical currents control in excitable cells. The KV7 channels familiy consists of 5 members (KV7.1-KV7.5) and the genes that encode them are related to significant pathologies. The structure of KV7 channels shares the usual six transmembrane segment structure, with intracellular the N- and C-termini. In neurons, KV7.2 and KV7.3 are the main channels, which generate the M-current that controls neuronal excitability. The M-current regulation is complex as it can be regulated by different signalling pathways. It is regulated by Gq/11-coupled receptors, and the signaling pathway depends on the activated receptor. Thus, the M1 muscarinic acetylcholine receptor inhibits KV7.2 current by PIP2 depletion. While the bradykinin receptor inhibits it through the calcium concentration increase driven by IP3. Among these mechanisms several proteins are involved, such as calmodulin, protein kinases and anchor proteins. In this review we will focus on KV7.2 channel, as it is involved in several diseases and for its complex regulation it can be an interesting target from a pharmacological point of view.