Functions and mechanisms of RNA helicases in plants.

RNA helicases (RHs) are a family of ubiquitous enzymes that alter RNA structures and remodel ribonucleoprotein complexes (RNPs) using the energy typically through hydrolysis of adenosine 5'-triphosphate (ATP). RHs are involved in various aspects of RNA processing and metabolism, exemplified by transcriptional regulation, pre-mRNA splicing, miRNA biogenesis, liquid-liquid phase separation, and rRNA biogenesis among other molecular processes. Through these mechanisms, RHs contribute to vegetative and reproductive growth, as well as abiotic and biotic stress responses throughout the life cycle in plants. In this review, we systematically characterized RH-featured domains and signature motifs in Arabidopsis. We also summarized the functions and mechanisms of RHs in various biological processes in plants with a focus on DEAD-box and DEAH-box RNA helicases, aiming to present the latest pictures of RHs in plant biology.