Purification from rat sarcolemma of the saxitoxin-binding component of the excitable membrane sodium channel.
AUTOR(ES)
Barchi, R L
RESUMO
The saxitoxin-binding component (SBC) of the excitable membrane sodium channel has been solubilized and purified from rat skeletal muscle sarcolemma. Phospholipid was required in mixed micelles with detergent for stability of the mammalian SBC. Even at optimal detergent-to-phospholipid ratio, the solubilized SBC showed significant temperature-dependent loss of specific toxin binding with time, necessitating maintenance of low temperatures during purification. Characteristics of saxitoxin binding to the solubilized material closely resembled those seen in intact membranes. A weak anion-exchange column was synthesized; it provided rapid 10- to 20-fold purification of the solubilized SBC. Additional necessary purification was obtained by chromatography on immobilized wheat germ agglutinin. Specific saxitoxin-binding activity of the purified material averaged approximately 1500 pmol of saxitoxin bound per mg of protein. Three bands were present in this material on sodium dodecyl sulfate/polyacrylamide gel electrophoresis. The purified material sedimented on a sucrose gradient with an apparent s20,w of 9.9 S.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=348483Documentos Relacionados
- Isolation and characterization of a monoclonal antibody against the saxitoxin-binding component from the electric organ of the eel Electrophorus electricus.
- Purification of the saxitoxin receptor of the sodium channel from rat brain.
- Functional reconstitution of the purified sodium channel protein from rat sarcolemma.
- Detergent extraction of a presumptive gating component from the voltage-dependent sodium channel.
- Purification of the tetrodotoxin-binding component associated with the voltage-sensitive sodium channel from Electrophorus electricus electroplax membranes.
