4OS ribosomal protein from a Saccharomyces cerevisiae antisuppressor mutant exhibiting a unique 2D gel pattern.

The yeast antisuppressor mutation, asu9-1 (Liebman and Cavenagh 1980) was found to cause an alteration in the 40S ribosomal subunit. Two-dimensional polyacrylamide gel electrophoresis patterns of the 40S ribosomal proteins from four different strains bearing the asu9-1 mutation all contained the same extra protein spot which was completely absent in five strains which did not carry the asu9 mutation.