TRNA lost in translation

Abstract

Molecular Biology Transfer RNAs (tRNAs), the adaptor molecules between messenger RNAs (mRNAs) and ribosomes during translation, are subjected to various types of chemical modifications, one of which is N 7--methylguanosine (m7G). Mutations in the human m7G methyltransferase complex lead to developmental disorders such as microcephalic primordial dwarfism and Down syndrome. Lin et al. mapped the m7G tRNA methylome at single-nucleotide resolution and demonstrated its essential role in mouse embryonic stem cells. Depletion of members of the m7G methyltransferase complex resulted in increased ribosome pausing on, and inefficient translation of, mRNAs involved in the cell cycle and brain development, thereby disrupting differentiation to neural lineages. This study is an important step toward a fuller understanding of how defects in tRNA methylation cause neurodevelopmental disorders. Mol. Cell 10.1016/j.molcel.2018.06.001 (2018).