Inositol phospholipid metabolism in Xenopus oocytes mediated by endogenous G(o) and Gi proteins.
To characterize G-proteins which mediate the signal transduction from ligand stimulated receptor to phospholipase C (PLC), we injected antisense DNAs complementary to Xenopus G(o) alpha or Gi-l alpha to suppress these endogenous G-proteins, together with the mRNAs encoding metabotropic glutamate receptor 1 (mGluR1), 5 (mGluR5) or with M1 type muscarinic receptor into oocytes. Receptor-stimulated chloride current responses were reduced by the suppression of Xenopus G(o) alpha regardless of the types of receptors. However, injection of Gi-1 antisense DNA resulted in the reduction of M1-stimulated responses but not mGluR-stimulated responses. These results suggested that all these receptors could use G(o) alpha, and M1 receptors, but not mGluRs, could also use Gi-1 proteins, to activate PLC in Xenopus oocytes.
Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan.
J
J
Kasahara
H
H
Sugiyama
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001483:Base Sequence; D018118:Chloride Channels / Q000378:metabolism; D004789:Enzyme Activation; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018698:Glutamic Acid / Q000494:pharmacology; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense; D009865:Oocytes; D010716:Phosphatidylinositols / Q000378:metabolism*; D011813:Quinuclidinyl Benzilate / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D018094:Receptors, Metabotropic Glutamate / Q000235:genetics / Q000378:metabolism; D011976:Receptors, Muscarinic / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D010738:Type C Phospholipases / Q000378:metabolism*; D014981:Xenopus
D018118:Chloride Channels; D016376:Oligonucleotides, Antisense; D010716:Phosphatidylinositols; D012333:RNA, Messenger; D018094:Receptors, Metabotropic Glutamate; D011976:Receptors, Muscarinic; D018698:Glutamic Acid; D011813:Quinuclidinyl Benzilate; D015544:Inositol 1,4,5-Trisphosphate; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D000109:Acetylcholine