Proteins of the turkey erythrocyte membrane

Abstract

A new and simplified method was described for preparation of turkey erythrocyte membranes which were essentially devoid of supernatant or nuclear contamination, but retained catecholamine-sensitive adenylate cyclase activity. These membranes were solubilized in sodium dodecyl sulfate and analyzed by polyacrylamide gel electrophoresis and the major protein components identified. The turkey erythrocyte membranes exhibited a protein profile similar to that of the human erythrocyte membrane, but contained a protein component of apparent MW of 50,000 which was not present in the human membranes. Three surface glycoprotein components of the turkey erythrocyte membranes (apparent MW of 90,000, 41,000 and 26,000) were identified by periodic acid-Schiff staining of polyacrylamide gels and by cell surface 125I labeling using lactoperoxidase followed by polyacrylamide gel electrophoresis. After deoxycholate solubilization of membranes prepared from iodinated cells, glycoproteins with MW 90,000 and 41,000 bound to an affinity column of concanavalin A-Sepharose 4B and eluted upon application of methyl .alpha.-D-mannopyrannoside. The lowest MW glycoprotein component did not bind to the insolubilized concanavalin A.