Actin-binding Protein Contributes to Cell Volume Regulatory Ion Channel Activation in Melanoma Cells

HORACIO F. CANTIELLO, ADRIANA G. PRAT, JOSEPH V. BONVENTRE, C. CASEY CUNNINGHAM, JOHN H. HARTWIG AND DENNIS A. AUSIELLO

JOURNAL OF BIOLOGICAL CHEMISTRY

Año: 1993 p. 4596 - 4599

0021-9258

The cell volume regulatory response to a hypotonic stimulus is frequently initiated by activation of K+ and C1- channels. We have characterized the hypotonic cell volume regulatory response of human melanoma cells devoid of actin-binding protein (ABP) and their genetically rescued counterpart transfected with the cDNA for ABP. ABP-deficient cells were unable to volumeregulate or activate K+ channels when exposed to a hypotonic stimulus. Genetic rescue with ABP resulted in recovery of both the cell volume regulatory response and the osmotically linked K+ channel activation. These data are consistent with a functional interaction between the actin cytoskeleton and osmotically sensitive ion transport.