Connecting emerging with existing vasculature above and below ground

The vascular system was essential for plants to colonize land by facilitating the transport of water, nutrients, and minerals throughout the body. Our current knowledge on the molecular-genetic control of vascular tissue specification and differentiation is mostly based on studies in the Arabidopsis primary root. To what degree these regulatory mechanisms in the root meristem can be extrapolated to vascular tissue development in other organs is a question of great interest. In this review, we discuss the most recent progress on cotyledon vein formation, with a focus on polar auxin transport-dependent and -independent mechanisms. We also provide an overview of vasculature formation in postembryonic organs, namely lateral roots, which is more complex than anticipated as several tissues of the parent root must act in a spatiotemporally coordinated manner.

Automated summary

The vascular system plays a crucial role in the growth and reproduction of plants by transporting water, nutrients, and minerals throughout the plant body. While our understanding of the regulatory mechanisms in vascular tissue development is mainly based on studies in the primary root of Arabidopsis, it remains unclear to what extent these mechanisms apply to other organs. This review focuses on recent advances in the formation of cotyledon veins, with an emphasis on polar auxin transport-dependent and -independent mechanisms. We also provide an overview of vascular formation in postembryonic organs, particularly lateral roots, which involves the coordinated action of multiple tissues.