The SEEL motif and members of the MYB-related REVEILLE transcription factor family are important for the expression of LORELEI in the synergid cells of the Arabidopsis female gametophyte
The SEEL motif and members of the MYB-related REVEILLE transcription factor family are important for the expression of LORELEI in the synergid cells of the Arabidopsis female gametophyte
复制标题
DOI：
10.1007/s00497-021-00432-1
复制
发表时间：
2021-10-29
影响因子：
3.4
通讯作者：
Palanivelu, Ravishankar
中科院分区：
文献类型：
--
作者：
Noble, Jennifer A.;Seddon, Alex;Palanivelu, Ravishankar
在开花植物的双受精和种子形成之前，雌配子体珠孔末端的协胞细胞是花粉管和胚珠之间关键的细胞-细胞信号相互作用所必需的。Lorelei(LRE)编码一种可能的GPI锚定蛋白，主要在助细胞中表达，并与费洛尼亚(一种受体样激酶)一起控制接受助细胞的花粉管接收。然而，LRE在助细胞中的表达是如何被控制的，仍然没有得到很好的描述。我们确定了富含LRE和其他助细胞表达基因的候选顺式调控元件。LRE启动子中的一个候选基序(‘TAATCT’)是晚间元件基序的一个未鉴定变体，我们将其命名为短晚素样(SEEL)基序。LRE启动子SEEL基序的缺失或点突变导致报告基因在助细胞中的表达降低，表明SEEL基序在助细胞中对LRE的表达是重要的。此外，我们还发现，LRE的表达在Reveille(RVE)转录因子功能突变的丧失中降低，RVE转录因子是已知与SEEL和其他密切相关基序结合的时钟基因。我们认为RVE转录因子通过与LRE启动子中的SEEL基序结合来调节助细胞中LRE的表达。识别参与LRE表达的顺式调控元件和转录因子将为研究助细胞的基因调控网络奠定基础。
Synergid cells in the micropylar end of the female gametophyte are required for critical cell-cell signaling interactions between the pollen tube and the ovule that precede double fertilization and seed formation in flowering plants. LORELEI (LRE) encodes a putative GPI-anchored protein that is expressed primarily in the synergid cells, and together with FERONIA, a receptor-like kinase, it controls pollen tube reception by the receptive synergid cell. Still, how LRE expression is controlled in synergid cells remains poorly characterized. We identified candidate cis-regulatory elements enriched in LRE and other synergid cell-expressed genes. One of the candidate motifs ('TAATATCT') in the LRE promoter was an uncharacterized variant of the Evening Element motif that we named as the Short Evening Element-like (SEEL) motif. Deletion or point mutations in the SEEL motif of the LRE promoter resulted in decreased reporter expression in synergid cells, demonstrating that the SEEL motif is important for expression of LRE in synergid cells. Additionally, we found that LRE expression is decreased in the loss of function mutants of REVEILLE (RVE) transcription factors, which are clock genes known to bind the SEEL and other closely related motifs. We propose that RVE transcription factors regulate LRE expression in synergid cells by binding to the SEEL motif in the LRE promoter. Identification of cis-regulatory elements and transcription factors involved in the expression of LRE will serve as a foundation to characterize the gene regulatory networks in synergid cells.