Modulation of the Ca2+-activated Cl- channel by 14-3-3 epsilon

We have previously reported an association of 14-3-3 epsilon isoform with c almodulin. Using the voltage-clamp technique, the present study investigate d the potential role of 14-3-3 in modulating the Ca2+-activated Cl- channel (CaCC) endogenously expressed in Xenopus oocytes. Injection of 14-3-3 epsi lon antisense oligodeoxynucleotides resulted in potentiation of the ionomyc in-induced Cl- current, while 14-3-3 peptide and calmodulin inhibitor, W13, suppressed the antisense-potentiated current. The data suggest that 14-3-3 epsilon plays an inhibitory role in modulating the CaCC by interacting wit h the calmodulin-dependent pathway. The potential role of 14-3-3 epsilon in other tissues and its therapeutic potential for cystic fibrosis are discus sed. (C) 2000 Academic Press.