Properties of membrane-bound ribosomes in reticulocytes.

摘要: Abstract An average of 17% rabbit reticulocyte ribosomes are closely bound to the cell membrane. Evidence is presented indicate that membrane binding not an artifact. Membrane-bound differ in physical and chemical properties from free having a high coefficient sedimentation (greater than 400 S) protein RNA ratio 5:1) being relatively resistant breakdown by deoxycholate. The rapidly sedimenting ribonucleoprotein aggregates varies with degree maturity cell, greatest older cells. active synthesis both intact cell-free system, but activity less ribosomes. Their susceptibility inhibitors synthesis, such as puromycin, 10-3 m, or sodium fluoride, 10-2 do break down subunits after exposure EDTA, degradation pancreatic ribonuclease. Binding dependent upon magnesium ion concentration, component susceptible ribonuclease action presence peptidyl-transfer on data suggest may be involved mechanism ribosomal erythroid cell.