Signalling events employed in the hypertonic activation of cation channels in HeLa cells.
In the present study, the signalling network behind the hypertonic activation of cation channels in HeLa cells was analysed by use of various inhibitors. Channel activation was monitored in whole-cell patch-clamp recordings, whereas the role of the channel in cell volume regulation was determined by electronic cell sizing. It is found that channel activation and volume control probably employs tyrosine kinases, G-proteins, PLC, PKC and p38MAP kinase, and that the process appears to depend on an intact actin skeleton. In contrast, RhoA, PI 3-kinase, ERK 1/2, JNK 1/2 as well as the exocytotic insertion of channels into the plasma membrane are likely not part of the signalling machinery.
Wehner
Frank
F
Department of Cell Physiology, National Institute for Physiological Sciences, Okazaki, Japan.
Numata
Tomohiro
T
Subramanyan
Muthangi
M
Takahashi
Nobuyuki
N
Okada
Yasunobu
Y
D000199:Actins / Q000378:metabolism; D002412:Cations / Q000378:metabolism; D048429:Cell Size; D003599:Cytoskeleton / Q000378:metabolism; D005089:Exocytosis; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D006982:Hypertonic Solutions; D007473:Ion Channels / Q000378:metabolism*; D020935:MAP Kinase Signaling System; D008564:Membrane Potentials; D009994:Osmolar Concentration; D018408:Patch-Clamp Techniques; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D010738:Type C Phospholipases / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
D000199:Actins; D002412:Cations; D006982:Hypertonic Solutions; D007473:Ion Channels; C066737:RHOA protein, human; D019869:Phosphatidylinositol 3-Kinases; D011505:Protein-Tyrosine Kinases; D011493:Protein Kinase C; D048049:Extracellular Signal-Regulated MAP Kinases; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein