Binding of Myotoxin 'a' to Cultured Muscle Cells

摘要

The binding of radiolabeled myotoxin a to various cultured cell lines wasevaluated. One rat skeletal muscle-derived cell line, L8, bound substantially more myotoxin a than did all other cell lines examined. Several biophysical parameters of myotoxin a-L8 binding were determined. Binding was saturable with a moderate binding affinity. Scatchard analysis and Hill plots indicated a single class of binding sites. The binding was reversible. as demonstrated by chase experiments. Radiolabeled myotoxin a bound to the cell surface at a site inaccessible to the general protease pronase. Specificity and biological relevance of the binding was suggested by competition with unlabeled toxin and various peptides derived from the toxin. Biologically active peptides,