Goprotein as signal transducer in the pertussis toxin-sensitive phosphatidylinositol pathway
| Autor: | Donna J. Carty, Elena Padrell, Thomas M. Moriarty, Gila Omri, Ravi Iyengar, Emmanuel M. Landau |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
Microinjections
Inositol 1 4 5-Trisphosphate Pertussis toxin Xenopus laevis chemistry.chemical_compound Chlorides GTP-Binding Proteins Heterotrimeric G protein Muscarinic acetylcholine receptor Animals Inositol Virulence Factors Bordetella Phosphatidylinositol Receptor Multidisciplinary Phospholipase C Chemistry Thionucleotides Receptors Muscarinic Pertussis Toxin Biochemistry Guanosine 5'-O-(3-Thiotriphosphate) Type C Phospholipases Second messenger system Oocytes Calcium Guanosine Triphosphate Signal Transduction |
| Zdroj: | Nature. 343:79-82 |
| ISSN: | 1476-4687 0028-0836 |
| DOI: | 10.1038/343079a0 |
| Popis: | RECEPTORS stimulating phospholipase C do so through heterotrimeric GTP-binding proteins1,2 to produce two second messengers, inositol 1,4,5-trisphosphate (InsP3) and diacylgly-cerol1. In spite of the detailed understanding of phospholipase C structure3 and phosphatidyl inositol signalling1, the identity of the GTP-binding protein involved is so far unknown. To address this issue, we have used the Xenopus oocyte in which muscarinic receptors couple to phospholipase C through a pertussis toxin-sensitive GTP-binding protein2. In this cell, InsP3 mobilizes intracellular Ca21 to evoke a Cl-current. The magnitude of this Cl- current is proportional to the amount of InsP3 in the cell4, and therefore can be used as an assay for InsP3 production. We report here that the activated a-subunit of the GTP-binding protein G0, when directly injected into oocytes, evokes a Cl- current by mobilizing Ca2+ from intracellular InsP3-sensitive stores. We also show that holo-GO, when injected into oocytes, can specifically enhance the muscarinic receptor-stimulated Cl current. These data indicate that GO can serve as the signal transducer of the receptor-regulated phospholipase C inXenopus oocytes. |
| Databáze: | OpenAIRE |
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