Transcription factor ZmPLATZ2 positively regulate the starch synthesis in maize
Transcription factor ZmPLATZ2 positively regulate the starch synthesis in maize
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转录因子 ZmPLATZ2 正向调控玉米淀粉合成
DOI：
10.1007/s10725-020-00687-0
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发表时间：
2021-01-31
影响因子：
4.2
通讯作者：
Huang, Yubi
中科院分区：
文献类型：
--
作者：
Li, Hui;Wang, Yayun;Huang, Yubi
玉米是世界三大粮食作物之一，产量和品质都很高。淀粉占玉米种子重量的60%以上，对玉米的产量和品质都至关重要，其结构影响着作物的品质。淀粉合成酶I（SSI）对玉米胚乳中的大部分淀粉合成酶活性有贡献。深入了解玉米淀粉合成调控机制，将为提高玉米产量和品质提供机遇。本研究通过共表达分析，筛选出与淀粉合成相关的植物AT富集序列和锌结合蛋白（PLATZ）转录因子ZmPLATZ 2。半定量RT-PCR和qRT-PCR分析表明，ZmPLATZ 2在胚乳中有较高的表达，在授粉后12 d达到高峰。不同的处理表明，ZmPLATZ 2下调蔗糖的存在。随后的反式激活和亚细胞定位分析表明，ZmPLATZ 2定位在细胞核中没有反式激活。酵母单杂交和玉米胚乳瞬时表达实验表明，ZmPLATZ 2可以与ZmSSI、ZmISA 1和ZmISA 2的启动子结合，提高它们的基因表达。ZmPLATZ 2在水稻中过表达后，包括OsSSI基因在内的四个淀粉合成基因在转基因植株中显著上调。体外DAP-seq数据显示ZmPLATZ 2可以结合CAAAAAAA元件。总之，我们的数据支持ZmPLATZ 2与ZmSSI启动子中的CAAAAAAA元件结合并介导Glu信号通路。
Maize is one of the three major crops worldwide based on its yield and quality. Starch is crucial to both the yield and quality of maize as it accounts more than 60% of the seed weight, and its structure influences the quality of the crop. Starch synthase I (SSI) contributes to the majority of the starch synthase activity in the maize endosperm. An in-depth understanding of the starch synthesis regulatory mechanism would provide opportunities for improving the yield and quality of maize. In this study,ZmPLATZ2, a plant AT-rich sequence and zinc-binding protein (PLATZ) transcription factor related to starch synthesis, was selected based on co-expression analysis. The semiquantitative RT-PCR and qRT-PCR assays revealed that ZmPLATZ2 had a high expression in the endosperm, and reached the peak at 12 days after pollination (DAP). Different treatments demonstrated that ZmPLATZ2 was downregulated by the presence of sucrose. Subsequent transactivation and subcellular localization analyses showed that ZmPLATZ2 was localized in the nuclei without transactivation. Yeast one-hybrid and transient expression in maize endosperm indicated that ZmPLATZ2 could bind to the promoters ofZmSSI,ZmISA1, andZmISA2and increase their gene expression. After ZmPLATZ2 overexpression in rice, four starch synthesis genes were significantly upregulated in the transgenic plant, including theOsSSIgene. In vitro DAP-seq data showed that ZmPLATZ2 could bind to the CAAAAAAA element. In conclusion, our data support that ZmPLATZ2 binds to the CAAAAAAA element in theZmSSIpromoter and mediates the Glu signal pathway.