UC San Diego

Protein translation is regulated at the stages of initiation, elongation, and termination. Under stress, translation is generally suppressed. Translation initiation has traditionally been thought of as the key control step of translation across a variety of stresses. Here we find that during glucose starvation in yeast, differential translation elongation is a crucial mechanism that allows preferential translation of select genes during stress. While these growth mRNAs have similar overall ribosome occupancy compared to these well-translated stress mRNAs, their distribution of ribosomes is skewed towards the 3’ end of the ORF. We also find that the skewed distribution in ribosomes during stress strongly correlates with increased mRNA binding by the DEAD-box RNA helicase, Dhh1. We speculate the recruitment of Dhh1 is associated with this differential protein translation upon glucose starvation. By regulating translation through elongation, cells could more dynamically control protein synthesis in adverse conditions.