State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, 430072, Wuhan, China.
State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China.
Nat Commun. 2019 Aug 2;10(1):3484. doi: 10.1038/s41467-019-11476-3.
Plant embryos are generated and develop in a stable and well-protected microenvironment surrounded by maternal tissue, which is vital for embryogenesis. However, the signaling mechanisms responsible for maternal tissue-to-proembryo communication are not well understood. Here, we report a pathway for maternal tissue-to-proembryo communication. We identify a DELLA protein, NtCRF1 (NtCYS regulative factor 1), which regulates suspensor programmed cell death (PCD). NtCRF1 can bind to the promoter of NtCYS and regulate the suspensor PCD-switch module NtCYS-NtCP14 in response to gibberellin (GA). We confirm that GA, as a primary signal triggering suspensor PCD, is generated in the micropylar endothelium by the transient activation of NtGA3oxs in the maternal tissue. Thus, we propose that GA is a maternal-to-proembryo communication signal that is decoded in the proembryo by a GID1-CRF1-CYS-CP14 signaling cascade. Using this mode of communication, maternal tissue precisely controls the embryonic suspensor PCD and is able to nurse the proembryo in a stage-dependent manner.
植物胚胎在母体组织包围的稳定且受保护的微环境中生成和发育，这对胚胎发生至关重要。然而，负责母体组织与原胚之间通讯的信号机制尚不清楚。在这里，我们报告了一个母体组织与原胚之间通讯的途径。我们鉴定了一种 DELLA 蛋白，NtCRF1（NtCYS 调节因子 1），它调节悬浮胚程序性细胞死亡（PCD）。NtCRF1 可以结合到 NtCYS 的启动子上，并响应赤霉素（GA）调节悬浮胚 PCD 开关模块 NtCYS-NtCP14。我们证实，GA 作为触发悬浮胚 PCD 的主要信号，是由母体组织中 NtGA3oxs 的瞬时激活在珠孔内皮层中产生的。因此，我们提出 GA 是一种母体到原胚的通讯信号，它在原胚中被 GID1-CRF1-CYS-CP14 信号级联解码。通过这种通讯模式，母体组织可以精确地控制胚胎悬浮胚程序性细胞死亡，并以依赖于胚胎阶段的方式滋养原胚。
