FIG. 8.

Sucrose gradient sedimentation analysis of PPR5-containing particles in stromal extract. Stromal extract was treated with RNase A or incubated under the same conditions in the absence of RNase and sedimented through sucrose gradients. An equal volume of each gradient fraction was analyzed on immunoblots probed with PPR5 antibody. Blots stained with Ponceau S are shown below. The last lane in each panel contains material that pelleted in the gradients. The position of ribosomes was determined by the pattern of Ponceau S-stained bands and by the appearance of rRNAs in these fractions (data not shown).