A voltage-dependent K⁺ channel in the lysosome is required for refilling lysosomal Ca²⁺ stores.

ABSTRACT: The resting membrane potential (Δψ) of the cell is negative on the cytosolic side and determined primarily by the plasma membrane's selective permeability to K⁺ We show that lysosomal Δψ is set by lysosomal membrane permeabilities to Na⁺ and H⁺, but not K⁺, and is positive on the cytosolic side. An increase in juxta-lysosomal Ca²⁺ rapidly reversed lysosomal Δψ by activating a large voltage-dependent and K⁺-selective conductance (LysoK_VCa). LysoK_VCa is encoded molecularly by SLO1 proteins known for forming plasma membrane BK channels. Opening of single LysoK_VCa channels is sufficient to cause the rapid, striking changes in lysosomal Δψ. Lysosomal Ca²⁺ stores may be refilled from end

SUBMITTER: Wang W 

PROVIDER: S-EPMC5461029 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature