Plant-specific ribosome biogenesis factors
January 2019. Ribosomes are the protein factories of the cell and thus essential to life. They are large multi-component complexes that consist of ribonucleic acids (rRNA) and proteins. The biogenesis of ribosomes is only partly understood. It is a highly complicated process coordinated by many biogenesis factors as the pre-ribosomal subunits acquire maturity on their route from the cell nucleolus to the cytoplasm.
In plants a well functioning ribosome biogenesis is not only essential for developmental but the regulation of ribosome biogenesis also has been linked to plant-specific signaling and stress responses. Ribosome assembly and processing has been best studied in yeast, a fungal model system, so far. Recent large scale bioinformatics and experimental studies have however shown that the ribosome biogenesis in plants differs significantly from that in yeast and the studies indicated the existence of plant-specific ribosome biogenesis factors (RBFs).
In their quest to understand the regulation of plant ribosome biogenesis a team of scientists at Frankfurt University led by Enrico Schleiff searched for plant-specific RBFs. The team characterized T-DNA insertion mutants of 15 Arabidopsis thaliana genes encoding nuclear proteins with nucleotide binding properties that are not orthologues to yeast or human RBFs. The researchers identified nine such proteins that play an important role in rRNA processing. Mutants of the nine genes showed changes ranging from inhibition of initial 35S pre-rRNA cleavage to final maturation events like the 6S pre-rRNA processing. Plants with these mutations were either not viable or exhibited developmental and stress-related phenotypes.
Denise Palm, Deniz Streit, Thiruvenkadam Shanmugam, Benjamin L Weis, Maike Ruprecht, Stefan Simm & Enrico Schleiff (2018) Plant-specific ribosome biogenesis factors in Arabidopsis thaliana with essential function in rRNA processing. Nucleic Acids Res: published online 19 December 2018. doi 10.1093/nar/gky1261
Enrico Schleiff, Buchmann Institute for Molecular Life Sciences and Institute of Molecular Biosciences, Goethe University, Riedberg Campus, Frankfurt/Main, Germany, schleiff(at)bio.uni-frankfurt.de.