OsPINOID Regulates Stigma and Ovule Initiation through Maintenance of the Floral Meristem by Auxin Signaling
OsPINOID Regulates Stigma and Ovule Initiation through Maintenance of the Floral Meristem by Auxin Signaling
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OsPINOID 通过生长素信号传导维持花分生组织来调节柱头和胚珠起始
DOI：
10.1104/pp.18.01385
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发表时间：
2019
期刊：
影响因子：
7.4
通讯作者：
Yu Hengxiu
中科院分区：
文献类型：
--
作者：
Xu Meng;Tang Ding;Cheng Xinjie;Zhang Jianxiang;Tang Yujie;Tao Qu;an;Shi Wenqing;You Aiqing;Gu Minghong;Cheng Zhukuan;Yu Hengxiu
柱头和胚珠的启动是开花植物有性繁殖所必需的。然而，柱头和胚珠原基发生的机制仍然不清楚。我们鉴定了一个水稻无柱头突变体，并揭示了它是由PINOID(OsPID)基因突变引起的。与在玉米(Zea Mays)和拟南芥(Arabitopsis Thaliana)中表现出典型的针状花序的拟南突变体不同，该突变体在花序发育和花起始过程中没有表现出任何缺陷，也不能在大多数小穗中发育正常的胚珠。幼龄雌蕊生长素活性低于野生型雌蕊。此外，大多数生长素反应因子基因的表达下调，OsETTIN1、OsETTIN2和OsMONOPTEROS在雌蕊和雄蕊原基发育过程中失去了表达模式的重排。此外，花分生组织标记基因OSH1的转录下调，而拟南芥CLAVATA3的同源基因花器官NUMBER4在Ospid雌蕊原基中上调。这些结果表明，雌蕊原基中的分生组织增殖可能被过早地阻止。基于这些结果，我们认为，OsPID介导的生长素信号通路通过维持花分生组织在调节水稻柱头和胚珠起始中发挥关键作用。
Stigma and ovule initiation is essential for sexual reproduction in flowering plants. However, the mechanism underlying the initiation of stigma and ovule primordia remains elusive. We identified a stigma-less mutant of rice (Oryza sativa) and revealed that it was caused by the mutation in thePINOID(OsPID) gene. Unlike thepidmutant that shows typical pin-like inflorescences in maize (Zea mays) and Arabidopsis (Arabidopsis thaliana), theospidmutant does not display any defects in inflorescence development and flower initiation, and fails to develop normal ovules in most spikelets. The auxin activity in the young pistil ofospidwas lower than that in the wild-type pistil. Furthermore, the expression of most auxin response factor genes was down-regulated, andOsETTIN1,OsETTIN2, andOsMONOPTEROSlost their rearrangements of expression patterns during pistil and stamen primordia development inospid. Moreover, the transcription of the floral meristem marker gene,OSH1, was down-regulated andFLORAL ORGAN NUMBER4, the putative ortholog of ArabidopsisCLAVATA3, was up-regulated in the pistil primordium ofospid. These results suggested that the meristem proliferation in the pistil primordium might be arrested prematurely inospid. Based on these results, we propose that the OsPID-mediated auxin signaling pathway plays a crucial role in the regulation of rice stigma and ovule initiation by maintaining the floral meristem.