Membrane potential dependent binding of scorpion toxin to action potential Na+ ionophore.
نویسندگان
چکیده
منابع مشابه
Membrane potential dependent binding of scorpion toxin to action potential Na+ ionophore.
Depolarization of neuroblastoma cells causes a 70-fold increase in the apparent dissociation constant KD for scorpion toxin enhancement of activation of the action potential Na+ ionophore by veratridine and a large increase in the rate of reversal of scorpion toxin action. Depolarization also inhibits binding of 125I-labeled scorpion toxin to a small number of saturable binding sites on electri...
متن کاملMembrane potential-dependent binding of scorpion toxin to the action potential Na+ ionophore. Studies with a toxin derivative prepared by lactoperoxidase-catalyzed iodination.
Scorpion toxin enhances activation of the action potential Na+ ionophore by the alkaloid neurotoxins veratridine, batrachotoxin, and aconitine. The pure toxin can be iodinated in a lactoperoxidase-catalyzed reaction. Both the monoiodoand diiodotoxin derivatives retain physiologic activity. Both monoiodoand diiodoscorpion toxin bind to a single class of saturable binding sites in electrically ex...
متن کاملPurification of a toxic protein from scorpion venom which activates the action potential Na+ ionophore.
Venom of the scorpion Leiurus quinquestriatus acts cooperatively with the alkaloids veratridine, aconitine, and batrachotoxin in activating the action potential Na+ ionophore. A small (Mr = 6700), basic (pI approximately 9.8), toxic polypeptide purified approximately 80-fold from this venom by ion exchange chromatography appears homogeneous by gel electrophoresis and isoelectric focusing and, l...
متن کاملCooperative activation of action potential Na+ ionophore by neurotoxins.
Four neurotoxins that activate the action potential Na+ ionophore of electrically excitable neuroblastoma cells interact with two distinct classes of sites, one specific for the alkaloids veratridine, batrachotoxin, and aconitine, and the second specific for scorpion toxin. Positive heterotropic cooperativity is observed between toxins bound at these two classes of sites. Tetrodotoxin is a nonc...
متن کاملSea anemone toxin and scorpion toxin share a common receptor site associated with the action potential sodium ionophore.
Toxin II isolated from the sea anemone Anemonia sulcata enhances activation of the action potential sodium ionophore of electrically excitable neuroblastoma cells by veratridine and batrachotoxin. This heterotropic cooperative effect is identical to that observed previously with scorpion toxin but occurs at a 110-fold higher concentration. Depolarization of the neuroblastoma cells inhibits the ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1976
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.73.8.2682