Research in Xuemei Chen’s lab centers on RNA. We have been using Arabidopsis thaliana as the model to uncover the machinery for RNA metabolism, reveal modes of action of regulatory RNAs, and understand how RNA-based molecular processes impact an organism’s biology. From 2001 to 2015, our efforts were mainly devoted to small RNAs, microRNAs (miRNAs) and small interfering RNAs (siRNAs). We studied how these small RNAs are made, degraded, and how they act in gene and genome regulation. Starting from 2015, we expanded our research portfolio and began to study certain reversible modifications of RNA and their biological impacts.