Characterization of the binding of rat liver ribosomal proteins L6, L8, L19, S9, and S13 to 5.8 S ribosomal ribonucleic acid.

The interaction of rat liver ribosomal proteins L6, L8, L19, S9, and S13 with 5.8 rRNA was characterized by nitrocellulose membrane filtration. Binding approached saturation with the five proteins; the apparent association constants (K'a), measured at 4 degrees C and 22 degrees C, ranged from 0.2 to 18 X 10(5) M-1. The molar ratio of ribosomal protein and rRNA in the complexes at saturation approximated 1, indicating there is one binding site for each of the five proteins on the nucleic acid. A number of ribosomal proteins, including some previously suspected from affinity chromatography of associating weakly, did not form a complex with 5.8 S rRNA.