Transcriptional buffering compensates for eIF4E deficiency 2 in mRNA translation in transformed but not normal cells

This study examined genome-wide translational and transcriptional regulation by the initiation factor eIF4E. The goals of the study were to understand how regulation differed between breast cancer and breast normal cells Stable MDA-MB-231 (breast cancer) and HMEC (breast normal) cells were created to inducibly express short-hairpin targeting eIF4E or a scrambled shRNA control upon addition of doxycycline. Cells were treated with doxycycline for 6 days and polysome gradient fractionation was performed. Polysome fractions were combined so that poorly expressed mRNA (2-3 ribosomes), moderately translated (4-6 ribosomes), highly translated (>6 ribosomes) mRNAs were analyzed. Total RNA prior to fractionation was also analyzed as a measure of total mRNA abundance.