Free and membrane-bound polyribosomes in normal and XXXX @entity19 spleen cells.

@entity778 @entity19 @entity73245 @entity35 @entity6743
1. Free and membrane-bound polyribosomes and ribosomal monomers were isolated from normal and @entity778 @entity19 spleens by means of discontinuous sucrose density gradients. 2. The addition of @entity73245 from @entity35 liver was essential to protect these polyribosomes from degradation. To separate the smooth and rough membranes from ribosomal monomers an additional centrifugation step through a continuous sucrose density gradient was necessary. 3. After infection a marked increase in rRNA from both membrane-bound and free polyribosomes was observed. Treatment of the membrane-bound polyribosomes with @entity6743 yielded only 80S particles even when @entity73245 was added. 4. A striking feature of the infected spleen was the occurrence of large polyribosomes. Up to 40 monomers per polyribosome could be counted on electron micrographs.
