Stimulation-induced modifications in Go proteins examined in giant fused synaptosomes.
Synaptoneurosomes (1-3 microm in diameter), prepared from rat brain stem or brain cortex, were fused with liposomes, producing a high yield of giant synaptosomes (10-60 microm in diameter). Single channel currents were measured by using the cell-attach patch-clamp technique. The membrane of the majority of these giant synaptosomes retained the cell membrane selective permeability. However, nonpermeating molecules, such as guanine nucleotides and antibodies directed against GTP-binding region in the alpha-subunit of trimeric GTP-binding proteins, were trapped in the giant synaptosomes during their preparation. Activation of Go proteins was assayed in high [K(+)]-depolarized giant synaptosomes, indicating the advantage of this preparation for tracing signal-transduction mechanisms in stimulated synaptic membranes. Stimulation-induced interactions between membrane proteins, either native or reconstituted, can be studied in the giant synaptosomes.
Dekel
Noya
N
The Neufeld Cardiac Research Institute, Sackler School of Medicine, Tel-Aviv University, 69978 Tel-Aviv, Israel.
Visochek
Leonid
L
Anis
Yosef
Y
Cohen-Armon
Malka
M
D020727:ADP-Ribosylation Factors / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001921:Brain / Q000378:metabolism*; D004558:Electric Stimulation; D019206:GTP-Binding Protein alpha Subunits, Gi-Go; D006150:Guanine Nucleotides / Q000494:pharmacology; D020962:Heterotrimeric GTP-Binding Proteins / Q000187:drug effects / Q000378:metabolism*; D008081:Liposomes; D008297:Male; D018408:Patch-Clamp Techniques; D037342:Pertussis Toxin / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D017729:Presynaptic Terminals / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013570:Synaptic Membranes / Q000187:drug effects / Q000378:metabolism*; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism*
D000906:Antibodies; D006150:Guanine Nucleotides; D008081:Liposomes; D037342:Pertussis Toxin; D019206:GTP-Binding Protein alpha Subunits, Gi-Go; D020962:Heterotrimeric GTP-Binding Proteins; D020727:ADP-Ribosylation Factors; D011188:Potassium