Lost in translation of genetic information? Back to the beginning to pinpoint translation initiators
A mRNA is a stretch of letters (i.e. A/U/C/G nucleotides), which contains genetic information to build proteins. Similar to the “text translation” (i.e. translating texts from one language to another), the process of using mRNA sequence information to produce proteins is called “mRNA translation” in biology. Thus, “translation initiation” mechanism, which controls where, when, and how translation events start, plays a critical role of shaping proteomes and controlling gene expressions for plant stress response/adaptation. Dr. Ming-Jung Liu group at the Agricultural Biotechnology Research Center systemically discovered a number of novel initiation sites across plant species, which were under appreciated in previous studies. These novel initiation sites were associated with mRNA translation repression and also contribute to the expression of distinct protein isoforms, which consequently affected protein organelle localizations. Intriguingly, while these initiation sites were generally found in orthologous gene pairs, the sequences of initiation sites were not conserved. These findings uncovered the hidden coding potential of plant genomes and, importantly, the constraint and flexibility of translation initiation mechanisms in the regulation of gene expression across plant species.