背景回顾：Development of plant organs is a highly organized process. In Arabidopsis, proper root development requires that distinct cell types and tissue layers are specified and formed in a restricted manner in space and over time. 

提出问题：Despite its importance, genetic controls underlying such regularity remain elusive. 

主要发现：Here we found that WIP genes expressed in the embryo and suspensor functionally oppose those expressed in the surrounding maternal tissues to orchestrate cell division orientation and cell fate specification in the embryonic root, thereby promoting regular root formation. 

结果：The materna WIPs act non-cell autonomously to repress root cell fate specification through SIMILAR TO RADICAL-INDUCED CELL DEATH ONE (SRO) family members. When losing all WIPs, root cells divide irregularly in the early embryo, but this barely alters their fate specification and the morphology of post-embryonic roots. 

结论：Our results reveal cross-communication between the embryonic and maternal WIPs in controlling root development.

 摘 要 

植物器官的发育是一个高度有序的过程。在拟南芥中，正确的根发育需要在时空限制条件下特化和形成的不同细胞类型和组织层。尽管该过程十分重要，但是调控该过程的遗传机制还不清楚。本文中，作者发现在胚胎和胚柄中表达的WIP基因与胚胎周边母体组织中表达的WIP基因呈相反作用，作用于胚根中的细胞分裂方向和细胞命运决定，从而促进规则的根形成。母体组织中的WIPs以非细胞自主性的方式，通过SRO家族成员来抑制根细胞命运特化。通过突变所有的WIP基因，早期胚胎中根细胞的分裂出现异常，但是这对于根细胞的命运特化以及胚后根的形态几乎没有影响。本文的研究结果揭示了胚胎和母体组织中的WIPs协同作用于根发育调控。