Actin-binding protein contributes to cell volume regulatory ion channel activation in melanoma cells.
The cell volume regulatory response to a hypotonic stimulus is frequently initiated by activation of K+ and Cl- 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 volume-regulate 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.
Renal Unit, Massachusetts General Hospital, Charlestown 02129.
H F
HF
Cantiello
A G
AG
Prat
J V
JV
Bonventre
C C
CC
Cunningham
J H
JH
Hartwig
D A
DA
Ausiello
D048429:Cell Size; D018118:Chloride Channels; D002712:Chlorides / Q000378:metabolism; D006801:Humans; D008545:Melanoma; D008564:Membrane Potentials; D008565:Membrane Proteins / Q000378:metabolism; D008840:Microfilament Proteins / Q000378:metabolism*; D009994:Osmolar Concentration; D015221:Potassium Channels / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D018118:Chloride Channels; D002712:Chlorides; D008565:Membrane Proteins; D008840:Microfilament Proteins; D015221:Potassium Channels