Stac3 enhances expression of human Ca_V1.1 in Xenopus oocytes and reveals gating pore currents in HypoPP mutant channels.

ABSTRACT: Mutations of Ca_V1.1, the pore-forming subunit of the L-type Ca²⁺ channel in skeletal muscle, are an established cause of hypokalemic periodic paralysis (HypoPP). However, functional assessment of HypoPP mutant channels has been hampered by difficulties in achieving sufficient plasma membrane expression in cells that are not of muscle origin. In this study, we show that coexpression of Stac3 dramatically increases the expression of human Ca_V1.1 (plus α₂-δ_1b and β_1a subunits) at the plasma membrane of Xenopus laevis oocytes. In voltage-clamp studies with the cut-open oocyte clamp, we observe ionic currents on the order of 1 μA and gating charge displacements of ∼0.5-1 nC. Importantly, this high expression level is suffi

SUBMITTER: Wu F 

PROVIDER: S-EPMC5839724 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature