Phosphatidylinositol 4,5-bisphosphate (PIP₂) regulates KCNQ3 K⁺ channels by interacting with four cytoplasmic channel domains.

ABSTRACT: Phosphatidylinositol 4,5-bisphosphate (PIP₂) in the plasma membrane regulates the function of many ion channels, including M-type (potassium voltage-gated channel subfamily Q member (KCNQ), K_v7) K⁺ channels; however, the molecular mechanisms involved remain unclear. To this end, we here focused on the KCNQ3 subtype that has the highest apparent affinity for PIP₂ and performed extensive mutagenesis in regions suggested to be involved in PIP₂ interactions among the KCNQ family. Using perforated patch-clamp recordings of heterologously transfected tissue culture cells, total internal reflection fluorescence microscopy, and the zebrafish (Danio rerio) voltage-sensitive phosphatase to deplete PIP₂ as a probe, we found that

SUBMITTER: Choveau FS 

PROVIDER: S-EPMC6302169 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature