Contrasting requirements for 4E-BP expression or eIF2α phosphorylation for inhibition of protein synthesis by Ku 0063794 under normal and hypertonic conditions.

The indicated cell lines were pre-incubated in complete medium in the absence or presence of additional 0.1 M NaCl. After 1 h the cells were further incubated with or without Ku-0063794 (1 M) for 1 h and total protein synthesis was then measured by the incorporation of [35S]methionine (2 µCi/ml) for 1 h as described in Experimental. The data are the means of 6–9 independent determinations. Asterisks show the significance of the differences between the effects of Ku-0063794 on protein synthesis under normal versus hypertonic conditions.