ATLA::Alternatives to Laboratory Animals

Volume 23, Number 4

Gap junctional intercellular communication and modulators of kinases and phosphatases.

ATLA 23, 480-484, July/August 1995

Trine Husøy, Svein-Ole Mikalsen and Tore Sanner

Laboratory for Environmental and Occupational Cancer, Institute for Cancer Research, The Norwegian Radium Hospital, N-0310 Oslo, Norway

SUMMARY

Seven phosphatase inhibitors were used to investigate the possible importance of phosphatases in the regulation of gap junctional intercellular communication (GJIC). Only the tyrosine phosphatase inhibitor, pervanadate, was found to inhibit GJIC and to alter the band pattern of connexin43 (Cx43) in Western blots. Only the unphosphorylated band of Cx43 was seen after alkaline phosphatase treatment of pervanadate-exposed cells. Application of a tyrosine-specific phosphatase and a phosphotyrosine antibody clearly indicated that pervanadate induced tyrosine phosphorylation in Cx43.

Keywords: gap junctional intercellular communication, phosphatase inhibitors, connexin43, tyrosine phosphorylation