K_Ca2 channel localization and regulation in the axon initial segment.

ABSTRACT: Small conductance calcium-activated potassium (K_Ca2) channels are expressed throughout the CNS and play a critical role in synaptic and neuronal excitability. K_Ca2 channels have a somatodendritic distribution with their highest expression in distal dendrites. It is unclear whether K_Ca2 channels are specifically present on the axon initial segment (AIS), the site at which action potentials are initiated in neurons. Through a powerful combination of toxin pharmacology, single-molecule atomic force microscopy, and dual-color fluorescence microscopy, we report here that K_Ca2 channels-predominantly the K_Ca2.3 subtype-are indeed present on the AIS. We also report that cAMP-PKA controls the axonal K_Ca2 channel surface expression. S

SUBMITTER: Abiraman K 

PROVIDER: S-EPMC5893165 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature