Figure 6.

Fractionation of mitochondrial ribonucleoprotein complexes. Total mitochondrial protein solubilized in the absence (A) and presence (B) of 300 mm KCl was fractionated on discontinuous Suc gradients. Fraction 1 corresponds to the sample buffer loaded onto the gradient. Fraction 2 corresponds to 15% Suc, 3 to 20%, 4 to 25%, 5 to 30%, 6 to 35%, 7 to 40%, 8 to 45%, 9 to 50%, and 10 to 55% Suc, respectively. Proteins of fractions 1 to 9 were analyzed by immunodetection with the @PMH1/PMH2 antibody. RNA of fractions 1 to 10 was inspected by agarose gel electrophoresis and ethidium bromide staining (RNA). Fractionation was done in buffer optimized for the separation of intact ribosomes and polysomes. Positions of 26S rRNA (26S) and 18S rRNA (18S) are indicated.