Cell cycle dependent regulation and function of ARGONAUTE1 in plants (Plant Cell) ($)

Regulation of gene expression at transcriptional, translational and post-translation levels is crucial for proper plant growth. Post-transcriptional gene regulation by small RNAs like microRNA (miRNA), siRNA and phasi-RNAs is necessary for meristem maintenance in plants. Unlike in the mammalian system, the role of small RNAs during the cell cycle in meristematic tissue is unknown. In this paper, Trolet et al. generated a large scale dataset that shines more light on small RNAs and specific regulators associated with ARGONAUTE1, which is involved in small RNA biogenesis. The loss of function ago1 mutants have altered meristem maintenance, and modulating AGO1 degradation during different phases of cell cycle causes changes in cell division at the Arabidopsis root meristem. Tobacco BY-2 cells were used to determine differentially expressed protein-coding mRNAs, small RNAs and cleaved target mRNAs at different stages of cell cycle. The miRNAs and differentially expressed genes that were identified from this study need to be further investigated for their roles in the cell cycle. (Summary by Suresh Damodaran) Plant Cell 10.1105/tpc.19.00069.