XinJiang Academy of Agricultural Sciences Grain Crops Institute, No. 403 Nanchang Road, Urumqi, 830091, China.
Biotechnology Research Institute of Chinese Academy of Agricultural Sciences, No. 12 Zhong Guan Cun South Street, Beijing, 100081, China.
Planta. 2021 Nov 24;254(6):130. doi: 10.1007/s00425-021-03770-6.
A Populus euphratica NAC gene regulates (1,3; 1,4)-β-D-glucan content in oat developing seed and improves the spikelet number and grain number per spike in transgenic oat under salinity conditions Salinity is the major factor affecting the production and quality of oat, and improving oat salt tolerance to increase yield and quality is vital. (1,3;1,4)-β-D-glucan in Gramineae is the key component in response to various environmental signals, and it is the most important functional ingredient in oat grain. The NAC transcription factors are important candidate genes used in genetic engineering to improve plant abiotic stress tolerance. In this study, we introduced Populus euphratica PeNAC1, controlled by its own promoter, into hexaploid cultivated oat and produced six transgenic lines. Compared to the non-transgenic control, the expression of PeNAC1 significantly improved the seed germination rate, seedling survival rate, and leaf chlorophyll content in the transgenic plants under salt stress. These physiological changes increased the spikelet number and grain number per spike in the transgenic oat under salinity conditions and reduced the yield loss per plant. The results indicated that the heterologous expression of PeNAC1 plays an effective role in improving the salt tolerance in transgenic oat. In addition, overexpressing PeNAC1 significantly increased the (1,3;1,4)-β-D-glucan content as well as the expression level of the (1,3;1,4)-β-D-glucan biosynthetic genes AsCslF3, AsCslF6, and AsCslF9 in the transgenic lines under salt stress, which suggested that PeNAC1 regulates the synthesis of (1,3;1,4)-β-D-glucan. Our research should assist in the discovery of the diverse action modes of NAC proteins, while PeNAC1 will be useful for improving the salt tolerance and quality of oat through molecular breeding.
胡杨 NAC 基因调控 oat 发育种子中（1,3;1,4）-β-D-葡聚糖的含量，并提高转基因 oat 在盐胁迫下的小穗数和每穗粒数
盐度是影响 oat 生产和品质的主要因素，提高 oat 的耐盐性以增加产量和品质至关重要。禾本科植物中的（1,3;1,4）-β-D-葡聚糖是响应各种环境信号的关键成分，也是 oat 谷物中最重要的功能成分。NAC 转录因子是用于遗传工程提高植物非生物胁迫耐受性的重要候选基因。在这项研究中，我们将胡杨 PeNAC1 引入六倍体栽培 oat 中，由其自身启动子控制，并产生了六个转基因系。与非转基因对照相比，PeNAC1 的表达在盐胁迫下显著提高了转基因植物的种子发芽率、幼苗存活率和叶片叶绿素含量。这些生理变化增加了转基因 oat 在盐胁迫下的小穗数和每穗粒数，并降低了每株植物的产量损失。结果表明，PeNAC1 的异源表达在提高转基因 oat 的耐盐性方面发挥了有效作用。此外，过表达 PeNAC1 显著增加了（1,3;1,4）-β-D-葡聚糖的含量以及（1,3;1,4）-β-D-葡聚糖生物合成基因 AsCslF3、AsCslF6 和 AsCslF9 在盐胁迫下的表达水平，这表明 PeNAC1 调节（1,3;1,4）-β-D-葡聚糖的合成。我们的研究应该有助于发现 NAC 蛋白的不同作用模式，同时 PeNAC1 将通过分子育种有助于提高 oat 的耐盐性和品质。
