National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Nanjing National Field Scientific Observation and Research Station for Rice Germplasm, Nanjing Agricultural University, Nanjing, 210095, China.
National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Nanjing National Field Scientific Observation and Research Station for Rice Germplasm, Nanjing Agricultural University, Nanjing, 210095, China; Faculty of Natural Sciences, Quynhon University, Quynhon, 590000, Binhdinh, Viet Nam.
Plant Physiol Biochem. 2023 Sep;202:107923. doi: 10.1016/j.plaphy.2023.107923. Epub 2023 Jul 31.
Seed dormancy is a critical trait that enhances plant survival by preventing seed germination at the wrong time or under unsuitable conditions. Lack of seed dormancy in rice can lead to pre-harvest sprouting on mother plants leading to reduced yield and seed quality. Although some genes have been identified, knowledge of regulation of seed dormancy is limited. Here, we characterized a weak seed dormancy mutant named weak seed dormancy 1 (wsd1) that showed a higher seed germination percentage than the wild-type following the harvest ripeness. We cloned the WSD1 encoding an aminotransferase protein using a MutMap approach. WSD1 was stably expressed after imbibition and its protein was localized in the endoplasm reticulum. A widely targeted metabolomics assay and amino acid analysis showed that WSD1 had a role in regulating homeostasis of amino acids. PAC treatment and RNA-seq analysis showed that WSD1 regulates seed dormancy by involvement in the GA biosynthesis pathway. GA content and expression of GA biosynthesis-related genes were increased in the wsd1 mutant compared with the wild-type. The wsd1 mutant had reduced sensitivity to ABA. Our overall results indicated that WSD1 regulates seed dormancy by balancing the ABA and GA pathways.
种子休眠是一种关键特性，它通过防止种子在错误的时间或不适宜的条件下发芽，从而增强植物的生存能力。水稻中缺乏种子休眠会导致母株在收获前发芽，从而降低产量和种子质量。虽然已经鉴定出一些基因，但对种子休眠调控的了解有限。在这里，我们描述了一个弱休眠突变体，命名为弱休眠 1（wsd1），与野生型相比，该突变体在收获成熟后表现出更高的种子发芽率。我们使用 MutMap 方法克隆了编码氨基转移酶蛋白的 WSD1。WSD1 在吸胀后稳定表达，其蛋白定位于内质网。广泛靶向的代谢组学分析和氨基酸分析表明，WSD1 在调节氨基酸的稳态方面发挥作用。PAC 处理和 RNA-seq 分析表明，WSD1 通过参与 GA 生物合成途径来调节种子休眠。与野生型相比，wsd1 突变体中的 GA 含量和 GA 生物合成相关基因的表达增加。wsd1 突变体对 ABA 的敏感性降低。我们的总体结果表明，WSD1 通过平衡 ABA 和 GA 途径来调节种子休眠。
