A second job for enzymes
Cells must be able to react to their environment for survival. They have to respond to internal cues such as timing of the cell cycle and outside stimuli including nutrient and oxygen levels. Some metabolic enzymes have been identified that can bind to RNA, that is, they can regulate gene expression. The EU-funded 'REM networks in yeast' (YREM) project has investigated the interactions between messenger RNAs (mRNAs), enzymes and metabolites (REM networks). Enzymes with a dual role catalyse reactions in processes involved with carbon metabolism such as glycolysis or fatty acid metabolism. By “freezing” RNA-protein reactions in vivo, the scientists singled out many mRNA-binding proteins (RBPs) in yeast cells. They were able to identify 678 RBPs with high confidence and many of these were previously unknown. Significant for evolution of metabolic systems, comparison with mammalian RBPs revealed more than 250 'ancient' RBPs in common between the two vastly different organisms. The scientists were also able to identify those RBPs that were solely mammalian and those that are yeast only. Project results have now verified that certain proteins involved in central carbon metabolism perform additional roles as RBPs. The next step is to reveal the mysteries of these networks in relation to their roles in cell function.
Keywords
Enzyme, protein, metabolic, mRNA, enzyme, metabolite, REM network, carbon metabolism, RBP, yeast, mammal, cell function
