Cyclin' Through the Root: Developmental Control of Cell Cycle Progression in the Arabidopsis thaliana Root Meristem

A plant's indeterminate growth requires constant cell proliferation and stem cell maintenance to support its developmental plasticity. The root meristem is an excellent system to study the developmental control of plant cell cycles due to the organ's accessibility and the tight link between cell cycle and developmental regulation. Studies have uncovered diverse pathways that shape root tissue patterning and cell identity, but how these mechanistically connect to cell cycle components remains unclear. Recent work and new approaches are starting to bridge this gap. In this review, we synthesize recent findings on the developmental regulation of cell cycle progression across distinct cell types and developmental zones in the Arabidopsis thaliana root apical meristem, highlighting cells and regions of the root where these processes have been thoroughly studied, and others where we know little. These discoveries reveal a nuanced relationship between cell identity and cell cycle regulation that implies an active role for cell cycle modulation in the patterning and developmental plasticity that are integral to plant growth.