Premium
Prostaglandin E 2 Induces Interaction Between hSlo Potassium Channel and Syk Tyrosine Kinase in Osteosarcoma Cells
Author(s) -
Rezzonico Roger,
SchmidAlliana Annie,
Romey Georges,
BourgetPonzio Isabelle,
Breuil Véronique,
Breittmayer Violette,
TartareDeckert Sophie,
Rossi Bernard,
SchmidAntomarchi Heidy
Publication year - 2002
Publication title -
journal of bone and mineral research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.882
H-Index - 241
eISSN - 1523-4681
pISSN - 0884-0431
DOI - 10.1359/jbmr.2002.17.5.869
Subject(s) - syk , tyrosine kinase , chemistry , microbiology and biotechnology , cancer research , tyrosine , proto oncogene tyrosine protein kinase src , phosphorylation , immunoreceptor tyrosine based activation motif , signal transduction , medicine , biochemistry , biology
Prostaglandins (PGs) are important mediators of bone response to growth factors, hormones, inflammation, or mechanical strains. In this study, we show that in MG63 osteosarcoma cells, prostaglandin E 2 (PGE 2 ) produces the opening of a large conductance Ca 2+ ‐dependent K + channel (BK). This PGE 2 ‐mediated channel opening induces the recruitment of various tyrosine‐phosphorylated proteins on the hSlo α‐subunit of BK. Because the C‐terminal domain of hSlo encompasses an immunoreceptor tyrosine‐based activation motif (ITAM), we show that the Syk nonreceptor tyrosine kinase, reported yet to be expressed mainly in hematopoietic cells, is expressed also in osteoblastic cells, and recruited on this ITAM after a PGE 2 ‐induced docking/activation process. We show that Syk/hSlo association is dependent of an upstream Src‐related tyrosine kinase activity, in accord with the classical two‐step model described for immune receptors. Finally, we provide evidence that this Syk/hSlo interaction does not affect the electrical features of BK channels in osteosarcoma cells. With these data, we would like to suggest the new notion that besides its conductance function, hSlo channel can behave in bone cells, as a true transduction protein intervening in the bone remodeling induced by PGE 2 .