Asynchronous termination of plasma membrane protein synthesis in erythroid cells.

In this study we focused our attention on the terminal stages of cellular differentiation and asked the question whether the turning off of gene activity is via a general mechanism whereby all proteins are turned off synchronously, or if it is regulated specifically. We examined this problem by measuring the relative rates of synthesis of the plasma membrane proteins in cells that are near the final stages of erythroid differentiation. Our results show that although the rates of synthesis of all proteins decline during maturation the relative rates of decline are different among the various membrane proteins, indicating that the termination of plasma membrane protein synthesis during terminal differentiation is asynchronous.