Translation efficiency is maintained at elevated temperature in E. coli

Cellular protein levels are dictated by the balance between gene transcription, mRNA translation and protein degradation, among other factors. Cells must manage their proteomes during stress; one way in which they may do so, in principle, is by differential translation. We used ribosome profiling to directly monitor translation in E. coli at 30 {degrees}C and investigate how this changes after 10-20 minutes of heat shock at 42 {degrees}C. Translation is controlled by the interplay of several RNA hybridization processes, which are expected to be temperature sensitive. However, translation efficiencies are robustly maintained after thermal heat shock and after mimicking the heat shock response transcriptional program at 30 {degrees}C. Several gene-specific parameters correlated with translation efficiency, including predicted mRNA structure and whether a gene is cotranslationally translocated into the inner membrane. Genome-wide predictions of the temperature dependence of mRNA structure suggest that relatively few genes show a melting transition between 30 {degrees}C and 42 {degrees}C, consistent with our observations. A linear model with five parameters can predict 33% of the variation in translation efficiency between genes, which may be useful in interpreting transcriptome data.