Possible coupling of prostaglandin E2 receptor with pertussis toxin-sensitive guanine nucleotide-binding protein in osteoblast-like cells.
In cloned osteoblast-like cells, MC3T3-E1, prostaglandin E2 (PGE2) stimulated the formation of inositol phosphates in a dose-dependent manner in the range between 10 nM and 10 microM. Pertussis toxin inhibited the effect of PGE2 dose-dependently in the range between 1 ng/ml and 1 micrograms/ml. In the cell membranes, pertussis toxin catalyzed ADP-ribosylation of a protein with an Mr of about 40,000. Pretreatment of membranes with 10 microM PGE2 in the presence of 2.5 mM MgCl2 and 100 microM GTP markedly attenuated this pertussis toxin-catalyzed ADP-ribosylation of the protein in a time-dependent manner. G12 was detected in these cells by immunoblotting with purified anti-G12 alpha antibodies. The results indicate the possible coupling of PGE2 signalling with pertussis toxin-sensitive GTP-binding protein, which is probably G12, in osteoblast-like cells.
Tokuda
H
H
First Department of Internal Medicine, Nagoya University School of Medicine, Aichi.
Kozawa
O
O
Yoneda
M
M
Oiso
Y
Y
Takatsuki
K
K
Asano
T
T
Kato
K
K
D002478:Cells, Cultured; D015232:Dinoprostone / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006868:Hydrolysis; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism*; D037342:Pertussis Toxin; D010716:Phosphatidylinositols / Q000378:metabolism*; D010740:Phospholipases / Q000378:metabolism; D011982:Receptors, Prostaglandin / Q000187:drug effects / Q000378:metabolism*; D018078:Receptors, Prostaglandin E; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
D010716:Phosphatidylinositols; D011982:Receptors, Prostaglandin; D018078:Receptors, Prostaglandin E; D010566:Virulence Factors, Bordetella; D037342:Pertussis Toxin; D010740:Phospholipases; D019204:GTP-Binding Proteins; D015232:Dinoprostone