Structural and Functional Aspects of Ribosome Interaction with Endoplasmic Reticulum Membranes

The different biochemical components of endoplasmic reticulum membranes (phospholipids, phosphoproteins and RNA) were investigated as to their ability to interact with the ribosomal protein and RNA. Light‐scattering determinations, viscosity measurements and gel‐filtration techniques were employed. A complex between a fraction of ribosomal protein (dialyzed against urea) and a phosphoprotein fraction from endoplasmic reticulum membranes, and a complex between a fraction of ribosomal protein (dialyzed against water) and two different phosphoprotein fractions from endoplasmic reticulum membranes, were obtained. No complexes could be detected between the other components under investigation. Likewise no complexes could be detected in the control experiments with lecithin, pepsin and cytochrome c, tested with ribosomal protein fractions and endoplasmic reticulum membranes phosphoproteins. These results suggest an additional new mechanism concerning the interaction of ribosomes with the endoplasmic reticulum membranes.