concanavalin-a and 3-((3-cholamidopropyl)dimethylammonium)-1-propanesulfonate

The prolactin, or lactogenic hormone, receptor has been purified (approximately 80%) from lactating mouse liver and human term placenta by the nondenaturing zwitterionic detergent 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate and a prolactin affinity column. The isolated "core-binding unit" has a molecular weight of 37,000 +/- 2,000 daltons. It retains the specificity for lactogenic hormones and binds prolactin with an affinity (Ka = 2 to 6 X 10(9) M-1) similar to that of the receptor as it occurs in its membranous environment (Ka = 3 to 5 X 10(9) M-1). Whether this "core-binding unit" exists on the cell surface in a cryptic or active form is influenced greatly by its association with other membrane proteins and the concentration of phosphatidylcholine within its local membranous environment.

Topics: Animals; Cholic Acids; Chromatography, Affinity; Concanavalin A; Electrophoresis, Polyacrylamide Gel; Female; Humans; Immunodiffusion; Liver; Mice; Mice, Inbred Strains; Microscopy, Electron; Microsomes; Microsomes, Liver; Models, Biological; Molecular Weight; Phospholipids; Placenta; Prolactin; Protein Binding; Rabbits; Rats; Rats, Inbred Strains; Receptors, Cell Surface; Receptors, Prolactin; Solubility