eIF5A depletion effect on synthesis and decay rates of yeast genes

In recent years, several components of the translational apparatus have been found in the nuclei of various eukaryotes, where they regulate transcription, processing or mRNA export, thus integrating different stages of gene expression. eIF5A is an essential and evolutionarily conserved translation elongation factor, which is involved in viral infection and in the development of diseases such as cancer and neurodevelopmental disorders. eIF5A promotes translation elongation by binding to ribosomes that stop at codons encoding amino acids problematic for peptide bond formation, such as consecutive prolines, also known as polyproline motifs.

Although eIF5A shuttles between the nucleus and the cytoplasm, its specific nuclear functions remain poorly defined. In this work we demonstrate that nuclear eIF5A from the yeast Saccharomyces cerevisiae binds to chromatin and represses gene transcription by preventing the binding of RNA polymerase II. Chromatin binding and transcriptional repression by eIF5A have a major impact on genes encoding their own translational targets.