Variations in the protein pattern of Ehrlich ascites tumor cell polyribosomes.

The two-dimensional gel electrophoretic protein pattern of polyribosomes from Ehrlich ascites tumor cells which have been fasted in a nutritionally deprived medium was compared to the corresponding pattern derived from unstarved cells. The proteins were labeled with 3H-labeled amino acids and their counts determined to make the comparison quantitative. Three proteins were found in the "fasted" polyribosomes in 4--6-fold greater amounts than in the fed control.