Lectures and seminars Fysiologföreningen presents: Professor Henrik Nielsen
Fysiologföreningen warmly welcome you to Professor Henrik Nielsen’s presentation on Ribosome specialization at the level of ribosomal RNA modifications.
'Ribosome specialization at the level of ribosomal RNA modifications'.
Professor Henrik Nielsen, Department of Cellular and Molecular Medicine, University of Copenhagen.
Ribosomes are the site of protein synthesis in all types of cells. It consists of a highly conserved core made of ribosomal RNA (rRNA) to which ribosomal proteins (RPs) are bound. It is well established that the cellular ribosome population is heterogeneous both at the level of rRNA and RPs. However, it has been difficult to address if this results in ribosomes with different properties. We are focusing on the most abundant rRNA modification, ribose methylation (2´OMe), and developed a sequencing-based method that allows profiling of the 112 2´OMe-sites in human rRNA. Differentiated tissues have very similar profiles with most, but not all, sites fully methylated. During development and cellular processes, such as T-cell activation, considerable changes in ribose methylation take place and perturbations of these have severe outcomes in cell fate. The method can be applied to samples from blood cancer patients and reveal overall hypomethylation of rRNA as well as specific growth-rate related changes in methylation pattern. At the mechanistic level, I will demonstrate how ablation of a single 2´OMe in HeLa cell rRNA changes the way the ribosomes translate the cellular mRNA pool and result in the re-programming of the cellular phenotype.