Reconstitution of the purified alpha-latrotoxin receptor in liposomes and planar lipid membranes. Clues to the mechanism of toxin action.

H. Scheer, G. Prestipino, J. Meldolesi

Research output: Contribution to journalArticle

Abstract

The receptor of alpha-latrotoxin (the major toxin of the black widow spider venom), purified from bovine synaptosomal membranes, was reconstituted into small unilamellar liposomes. These (but not control) liposomes exhibited high-affinity, specific binding of [125I]alpha-latrotoxin. In the receptor-bearing liposomes alpha-latrotoxin induced depolarization and stimulated 45Ca efflux. These responses to alpha-latrotoxin, that were observed only in the presence of external divalent cations, resembled those previously demonstrated in mammalian brain synaptosomes. The alpha-latrotoxin-activated ion fluxes are therefore, at least in part, the result of the direct interaction of the toxin with its receptor. When control and receptor-bearing liposomes were pre-incubated with alpha-latrotoxin and then added to a solution bathing a planar lipid bilayer membrane, single channel cationic conductances were observed. In the presence of the receptor, the conductances induced by alpha-latrotoxin were markedly different from those observed without the receptor, but not identical to those observed without the receptor, but not identical to those recently characterized by patch clamping in the cells of a line (PC12) sensitive to alpha-latrotoxin. These results demonstrate that the reconstituted receptor is functional, and suggest that the cationic channel activated by the toxin-receptor interaction is modulated by additional component(s) in the membrane of synapses and cells.

Original languageEnglish
Pages (from-to)2643-2648
Number of pages6
JournalEMBO Journal
Volume5
Issue number10
Publication statusPublished - Oct 1986

Fingerprint

Membrane Lipids
Liposomes
Bearings (structural)
Membranes
Unilamellar Liposomes
Lipid bilayers
Synaptosomes
Divalent Cations
Depolarization
Lipid Bilayers
alpha-latrotoxin receptor
alpha-latrotoxin
Ion Channels
Constriction
Synapses
Brain
Cell Membrane
Ions
Fluxes
Cell Line

ASJC Scopus subject areas

  • Cell Biology
  • Genetics

Cite this

Reconstitution of the purified alpha-latrotoxin receptor in liposomes and planar lipid membranes. Clues to the mechanism of toxin action. / Scheer, H.; Prestipino, G.; Meldolesi, J.

In: EMBO Journal, Vol. 5, No. 10, 10.1986, p. 2643-2648.

Research output: Contribution to journalArticle

@article{c53e9ff7ed2f43ed976355409ba63cd8,
title = "Reconstitution of the purified alpha-latrotoxin receptor in liposomes and planar lipid membranes. Clues to the mechanism of toxin action.",
abstract = "The receptor of alpha-latrotoxin (the major toxin of the black widow spider venom), purified from bovine synaptosomal membranes, was reconstituted into small unilamellar liposomes. These (but not control) liposomes exhibited high-affinity, specific binding of [125I]alpha-latrotoxin. In the receptor-bearing liposomes alpha-latrotoxin induced depolarization and stimulated 45Ca efflux. These responses to alpha-latrotoxin, that were observed only in the presence of external divalent cations, resembled those previously demonstrated in mammalian brain synaptosomes. The alpha-latrotoxin-activated ion fluxes are therefore, at least in part, the result of the direct interaction of the toxin with its receptor. When control and receptor-bearing liposomes were pre-incubated with alpha-latrotoxin and then added to a solution bathing a planar lipid bilayer membrane, single channel cationic conductances were observed. In the presence of the receptor, the conductances induced by alpha-latrotoxin were markedly different from those observed without the receptor, but not identical to those observed without the receptor, but not identical to those recently characterized by patch clamping in the cells of a line (PC12) sensitive to alpha-latrotoxin. These results demonstrate that the reconstituted receptor is functional, and suggest that the cationic channel activated by the toxin-receptor interaction is modulated by additional component(s) in the membrane of synapses and cells.",
author = "H. Scheer and G. Prestipino and J. Meldolesi",
year = "1986",
month = "10",
language = "English",
volume = "5",
pages = "2643--2648",
journal = "EMBO Journal",
issn = "0261-4189",
publisher = "Nature Publishing Group",
number = "10",

}

TY - JOUR

T1 - Reconstitution of the purified alpha-latrotoxin receptor in liposomes and planar lipid membranes. Clues to the mechanism of toxin action.

AU - Scheer, H.

AU - Prestipino, G.

AU - Meldolesi, J.

PY - 1986/10

Y1 - 1986/10

N2 - The receptor of alpha-latrotoxin (the major toxin of the black widow spider venom), purified from bovine synaptosomal membranes, was reconstituted into small unilamellar liposomes. These (but not control) liposomes exhibited high-affinity, specific binding of [125I]alpha-latrotoxin. In the receptor-bearing liposomes alpha-latrotoxin induced depolarization and stimulated 45Ca efflux. These responses to alpha-latrotoxin, that were observed only in the presence of external divalent cations, resembled those previously demonstrated in mammalian brain synaptosomes. The alpha-latrotoxin-activated ion fluxes are therefore, at least in part, the result of the direct interaction of the toxin with its receptor. When control and receptor-bearing liposomes were pre-incubated with alpha-latrotoxin and then added to a solution bathing a planar lipid bilayer membrane, single channel cationic conductances were observed. In the presence of the receptor, the conductances induced by alpha-latrotoxin were markedly different from those observed without the receptor, but not identical to those observed without the receptor, but not identical to those recently characterized by patch clamping in the cells of a line (PC12) sensitive to alpha-latrotoxin. These results demonstrate that the reconstituted receptor is functional, and suggest that the cationic channel activated by the toxin-receptor interaction is modulated by additional component(s) in the membrane of synapses and cells.

AB - The receptor of alpha-latrotoxin (the major toxin of the black widow spider venom), purified from bovine synaptosomal membranes, was reconstituted into small unilamellar liposomes. These (but not control) liposomes exhibited high-affinity, specific binding of [125I]alpha-latrotoxin. In the receptor-bearing liposomes alpha-latrotoxin induced depolarization and stimulated 45Ca efflux. These responses to alpha-latrotoxin, that were observed only in the presence of external divalent cations, resembled those previously demonstrated in mammalian brain synaptosomes. The alpha-latrotoxin-activated ion fluxes are therefore, at least in part, the result of the direct interaction of the toxin with its receptor. When control and receptor-bearing liposomes were pre-incubated with alpha-latrotoxin and then added to a solution bathing a planar lipid bilayer membrane, single channel cationic conductances were observed. In the presence of the receptor, the conductances induced by alpha-latrotoxin were markedly different from those observed without the receptor, but not identical to those observed without the receptor, but not identical to those recently characterized by patch clamping in the cells of a line (PC12) sensitive to alpha-latrotoxin. These results demonstrate that the reconstituted receptor is functional, and suggest that the cationic channel activated by the toxin-receptor interaction is modulated by additional component(s) in the membrane of synapses and cells.

UR - http://www.scopus.com/inward/record.url?scp=0022802629&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0022802629&partnerID=8YFLogxK

M3 - Article

C2 - 3780674

AN - SCOPUS:0022802629

VL - 5

SP - 2643

EP - 2648

JO - EMBO Journal

JF - EMBO Journal

SN - 0261-4189

IS - 10

ER -