TY - JOUR
T1 - Connexin channels, connexin mimetic peptides and ATP release
AU - Leybaert, Luc
AU - Braet, Katleen
AU - Vandamme, Wouter
AU - Cabooter, Liesbet
AU - Martin, Patricia E.M.
AU - Evans, W. Howard
N1 - Funding Information:
Research supported by the Fund for Scientific Research Flanders, Belgium (FWO, grant nos. 3G023599, 3G001201 and G.0335.03 to L.L.), the Belgian Society for Scientific Research in Multiple Sclerosis (WOMS, grant no. 51F06700 to L.L.), Ghent University (BOF, grant nos. 01115099, 01107101 and 01113403 to L.L.), and the Queen Elisabeth Medical Foundation (grant no. 365B5602 to L.L.).
PY - 2003
Y1 - 2003
N2 - Connexin hemichannels, that is, half gap junction channels (not connecting cells), have been implicated in the release of various messengers such as ATP and glutamate. We used connexin mimetic peptides, which are, small peptides mimicking a sequence on the connexin subunit, to investigate hemichannel functioning in endothelial cell lines. Short exposure (30 min) to synthetic peptides mimicking a sequence on the first or second extracellular loop of the connexin subunit strongly supressed ATP release and dye uptake triggered by either intracellular InsP3 elevation or exposure to zero extracellular calcium, while gap junctional coupling was not affected under these conditions. The effect was dependent on the expression of connexin-43 in the cells. Connexin mimetic peptides thus appear to be interesting tools to distinguish connexin hemichannel from gap junction channel functioning. In addition, they are well suited to further explore the role of connexins in cellular release or uptake processes, to investigate hemichannel gating and to reveal new unknown functions of the large conductance hemichannel pathway between the cell and its environment. Work performed up to now with these peptides should be re-interpreted in terms of these new findings.
AB - Connexin hemichannels, that is, half gap junction channels (not connecting cells), have been implicated in the release of various messengers such as ATP and glutamate. We used connexin mimetic peptides, which are, small peptides mimicking a sequence on the connexin subunit, to investigate hemichannel functioning in endothelial cell lines. Short exposure (30 min) to synthetic peptides mimicking a sequence on the first or second extracellular loop of the connexin subunit strongly supressed ATP release and dye uptake triggered by either intracellular InsP3 elevation or exposure to zero extracellular calcium, while gap junctional coupling was not affected under these conditions. The effect was dependent on the expression of connexin-43 in the cells. Connexin mimetic peptides thus appear to be interesting tools to distinguish connexin hemichannel from gap junction channel functioning. In addition, they are well suited to further explore the role of connexins in cellular release or uptake processes, to investigate hemichannel gating and to reveal new unknown functions of the large conductance hemichannel pathway between the cell and its environment. Work performed up to now with these peptides should be re-interpreted in terms of these new findings.
KW - ATP release
KW - Connexin hemichannels
KW - Cytoplasmic calcium
KW - Dye uptake
KW - Gap junction channels
KW - Zero extracellular calcium
U2 - 10.1080/cac.10.4-6.251.257
DO - 10.1080/cac.10.4-6.251.257
M3 - Article
C2 - 14681025
AN - SCOPUS:0346496120
SN - 1541-9061
VL - 10
SP - 251
EP - 257
JO - Cell Communication and Adhesion
JF - Cell Communication and Adhesion
IS - 4-6
ER -