Origin and function of the root vascular cambium ($) (Nature)

The vascular cambium is a meristematic tissue that is responsible for lateral growth and the continued production of new xylem and phloem; in woody plants, the shoot vascular cambium makes wood. A new pair of papers investigates how the Arabidopsis root vascular cambium forms and how it functions. Through mutant analysis and imaging, the authors unravel several interesting mechanisms for these processes; these include mobile cell-to-cell signals that inform cells about their neighbors and their positions, key roles for hormones, and antagonistically-functioning sets of transcription factors. Thus, a key finding is that although some of the specific players identified are new, the developmental programs involved in vascular cambium development and function follow similar ground rules as those that act in the primary root and shoot meristems. (Miyashima et al. 10.1038/s41586-018-0839-y and Smetana et al. 10.1038/s41586-018-0837-0.) Nature (Summary by Mary Williams)