Receptor-evoked Cl- current in Xenopus oocytes is mediated through a β- type phospholipase C. Cloning of a new form of the enzyme

H. W. Ma, R. D. Blitzer, E. C. Healy, R. T. Premont, E. M. Landau, R. Iyengar

Research output: Contribution to journalArticlepeer-review

31 Scopus citations

Abstract

Xenopus oocytes exhibit a receptor-evoked Cl- current that is mediated through the activation of phospholipase C (PLC) and release of intracellular Ca2+. The identity of PLC(s) mediating this effect is unknown. We have cloned cDNAs encoding a new form of PLC-β from a Xenopus oocyte cDNA library. The Xenopus PLC-β has substantial (33-64%) homology with mammalian β1, β2, β3, and β4 phospholipase C and is closest to PLC-β3, with 64% identity and 80% similarity. Injection of antisense oligonucleotides to a specific region of Xenopus PLC-β results in degradation of its mRNA and significantly reduces Cl- currents evoked by both endogenous angiotensin receptors and expressed mammalian α(1b)-adrenergic receptors and M1- muscarinic receptors as compared to responses in sense oligonucleotide- injected oocytes. Inhibition of the M1-muscarinic response by antisense oligonucleotides was nonadditive with pertussis toxin inhibition. PLC antisense oligonucleotide-injected oocytes show Cl- current responses to IP3 that are indistinguishable from sense oligonucleotide-injected oocytes. Since the receptor responses are pertussis toxin-sensitive, we conclude that we have isolated a new form of PLC-β involved in the pertussis toxin- sensitive receptor stimulation of the Ca2+ activated Cl- current in Xenopus oocytes.

Original languageEnglish
Pages (from-to)19915-19918
Number of pages4
JournalJournal of Biological Chemistry
Volume268
Issue number27
StatePublished - 1993

Fingerprint

Dive into the research topics of 'Receptor-evoked Cl- current in Xenopus oocytes is mediated through a β- type phospholipase C. Cloning of a new form of the enzyme'. Together they form a unique fingerprint.

Cite this