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 spatio-temporally coordinated manner.

维管系统通过促进水、营养物质和矿物质在体内的运输，对于植物在陆地上定居至关重要。我们目前对维管组织规范和分化的分子遗传控制的知识主要基于对拟南芥主根的研究。根分生组织中的这些调节机制在多大程度上可以外推到其他器官中维管组织的发育，这是一个令人非常感兴趣的问题。在这篇综述中，我们讨论了子叶静脉形成的最新进展，重点是极性生长素运输依赖和独立机制。我们还概述了胚胎后器官（即侧根）中脉管系统的形成，它比预期更复杂，因为母根的多个组织必须以时空协调的方式发挥作用。