New insights into the plant epitranscriptome

Throughout all kingdoms of life, ribonucleotides are marked with covalent chemical modifications that change the structure and binding properties of modified RNA molecules. These marks are deposited by 'writer' proteins, recognized by 'readers', and removed by 'erasers', thus forming an epitranscriptomic system of marks and binding proteins directly analogous to the epigenome. Recent advances in marrying classical biochemical techniques with high-throughput sequencing have enabled detailed mapping of plant epitranscriptomic marks, which in turn yielded insights into how these marks regulate a host of biological processes, from shoot stem cell fate to floral transition and from leaf development to viral activity. In this review, we highlight recent developments in the study of plant epitranscriptomics, with an emphasis on N6-methyladenosine (m6A) and 5-methylcytosine (m5C). These studies have advanced the field beyond descriptive mapping or isolated genetic studies, and produced a more nuanced understanding of how components of the epitranscriptome and their binding proteins directly regulate critical aspects of plant biology.