Noncanonical auxin signaling regulates cell division pattern during lateral root development

Significance Development in multicellular organisms consists of a series of cell divisions followed by cell expansions, which are tightly controlled both spatially and temporally. Disorganized cell division causes serious growth defects in both animals and plants. Auxin has been repeatedly implicated in regulating cell division patterns during organogenesis in plants; however, the underlying mechanisms remain to be further investigated. Here, we demonstrate that auxin signaling controls cell division pattern by activating Mitogen-Activated Protein Kinase (MAPK)-signaling cascade during lateral root development. Our work reveals how signal transduction pathways regulate cell division pattern and also provides a connection between auxin signaling and MAPK signaling in plants.