Fibronectin-integrin binding promotes hyperpolarization of murine erythroleukemia cells.

The resting electrical potential (delta psi p) of murine erythroleukemia cells (MELC) was measured by the patch-clamp technique at different times after seeding onto culture surfaces enriched with bovine serum albumin (BSA) or Fibronectin (FN). While BSA did not produce significant changes of potential and cell shape, FN promoted a 15-20 mV hyperpolarization that preceded a marked cell spreading. This hyperpolarization was abolished by either treating cells with anti FN-receptor antibodies, or adding the RGDS tetrapeptide, suggesting that electric signals are elicited by the specific interaction of the FN cell binding domain with integrin receptors.