提出问题：Previous studies have revealed that the phytohormone auxin plays a crucial role in somatic embryogenesis by inducing a cell totipotent state, although its underlying mechanism is poorly understood.

主要发现：Here, we show that auxin rapidly rewires the cell totipotency network by altering chromatin accessibility.

结果-染色质开放动态：The analysis of chromatin accessibility dynamics further reveals a hierarchical gene regulatory network underlying somatic embryogenesis.

结果-外植体：Particularly, we find that the embryonic nature of explants is a prerequisite for somatic cell reprogramming.

结果-LEC2-WOX2/3：Upon cell reprogramming, the B3-type totipotent transcription factor LEC2 promotes somatic embryo formation by direct activation of the early embryonic patterning genes WOX2 and WOX3.

结论：Our results thus shed light on the molecular mechanism by which auxin promotes the acquisition of plant cell totipotency and establish a direct link between cell totipotent genes and the embryonic development pathway.