The mechanism of channel regulation and gating is studied electrophysiologically at the single channel level in two-cell systems by double whole-cell patch clamp. The molecular domains that participate in channel gating are being defined by a multiple approach that combines molecular genetics, biophysics and fluorescence imaging. The effect of chimeric constructions and amino acid residue deletions or substitutions at crucial connexin domains are tested in pairs of Xenopus oocytes or small cultured cells by measuring junctional conductance and monitoring single channel behavior by double voltage clamp electrophysiology.

Peracchia, C.  (2004)  Chemical gating of gap junction channels - Roles of calcium, pH and calmodulin.  Biochim. Biophys. Acta 1662:61-80.

Peracchia, C., Chen, J.T., and Peracchia, L.L.  (2004)  CO2 sensitivity of voltage gating and gating polarity of gap junction channels - connexin40 and its COOH-terminus truncated mutant.  J. Membr. Biol. 200:105-113.

Young, K.C., and Peracchia, C.  (2004)  Opposite Vj gating polarity leads to opposite CO2 sensitivity of Cx32 and Cx26 voltage gating.  J. Membr. Biol. 202:161-170.

Kotsias, B.A., and Peracchia, C.  (2005)  Functional interaction between CFTR and Cx45 gap junction channels expressed in oocytes.  J. Membr. Biol. 203:143-150.

Peracchia, C., and Peracchia, L.L.  (2005)  Inversion of both gating polarity and CO2 sensitivity of voltage gating with D3N point mutation of connexin50.  Am. J. Physiol. Cell Physiol. 288:C1381-C1389.