Isolation and characterization of membrane proteins responsible for attachment of polyribosomes to rough microsomal fraction of rat liver.

Abstract

A protein fraction which has a high affinity for polyribosomes was isolated from rough microsomal membranes of rat liver. The mode of polyribosome binding to this fraction (R-fraction) was studied by using CsCl equilibrium centrifugation and compared with that for stripped rough microsomal membranes. The following were found. (1) The polyribosome-binding cpacity of the R-fraction was heat-labile and sensitive to trypsin, and was suppressed by increasing KCl concentration and addition of 0.1 mM-aurintricarboxylic acid. (2) Of the four subfractions obtained by gel filtration of the R-fraction on a Sephadex G-200, only the R1-fraction, eluted at the void volume, showed a high affinity for polyribosomes. The polyribosome-binding capacity of the R1-fraction decreased with time on storage at 4 degrees C. (3) The R1-fraction contained three major proteins with mol. wts. 108,000, 99,000 and 65,000.

Cite this paper

@article{Fujita1977IsolationAC, title={Isolation and characterization of membrane proteins responsible for attachment of polyribosomes to rough microsomal fraction of rat liver.}, author={Seiichi Fujita and Fukiko Ogata and Jiro Nakamura and Saburo Omata and Haruo Sugano}, journal={The Biochemical journal}, year={1977}, volume={164 1}, pages={53-66} }