Oxytocin receptor couples to the 80 kDa Ghα family protein in human myometrium
نویسندگان
چکیده
One of the primary functions of the oxytocin receptor is to modulate intracellular calcium levels in myometrium. The oxytocin receptor has been purified and cloned. Although it has been suggested that oxytocin receptor couples with a GTP-binding regulatory protein (G-protein), the identity of this G-protein remains unclear. To elucidate themechanism of oxytocin receptor signalling, we used the oxytocin–receptor–G-protein ternary complex preparation from human myometrium, and evaluated oxytocin-mediated activation of [$&S]guanosine 5«-[γthio]triphosphate ([$&S]GTP[S]) binding and [α-$#P]GTP photoaffinity labelling to a G-protein. Binding of [$&S]GTP[S] and the intensity of the [α-$#P]GTP photoaffinity labelled protein resul-
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