Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China.
College of Biology and Food Engineering, Anyang Institute of Technology, Anyang 455000, China.
Int J Mol Sci. 2022 Mar 5;23(5):2845. doi: 10.3390/ijms23052845.
As one of the pioneer crops widely planted in saline-alkaline areas, provides daily necessities, including natural fiber, vegetable proteins, and edible oils. However, cotton fiber yield and quality are highly influenced by salt stress. Therefore, elucidating the molecular mechanisms of cotton in response to salinity stress is importance to breed new cultivars with high tolerance. In this study, we first developed a method for single-cell RNA-seq based on isolating protoplast from cotton root tips; then, we studied the impact of salinity stress on gene expression profiling and their dynamic changes using the developed high-efficiency method for protoplast dissociation suitable for single-cell RNA-seq. A total of 3391 and 2826 differentially expressed genes (DEGs) were identified in salt-treated samples before and after protoplast dissociation, respectively, which were enriched into several molecular components, including response to stimulus, response to stress, and cellular macromolecule metabolic process by gene ontology (GO) analysis. Plant hormone signal transduction, phenylpropanoid biosynthesis, and MAPK signaling pathway were found to be enriched via Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Twenty-two and nine salinity-responsive DEGs participated in plant hormone signaling and MAPK signaling in roots, before and after protoplast dissociation, respectively; six upregulated DEGs were involved in ABA signaling transduction, namely, , , , , , and which indicates their potential functions on plants adapting to salt stress. Additionally, 384 and 257 transcription factors (TFs) were differentially expressed in salt-stress roots before and after protoplast dissociation, respectively, of which significantly up-regulated TFs mainly belonged to the AP2/ERF-ERF family, which implied their potential roles responding to salt stress. These results not only provide novel insights to reveal the regulatory networks in plant's root response to salt stress, but also lay the solid foundation for further exploration on cellular heterogeneity by single-cell transcriptome sequencing.
作为在盐碱地区广泛种植的先锋作物之一，棉花为人们提供了包括天然纤维、植物蛋白和食用油在内的生活必需品。然而，棉花纤维的产量和质量受盐胁迫的影响较大。因此，阐明棉花对盐胁迫的分子机制对于培育具有高耐盐性的新品种具有重要意义。本研究首先建立了一种基于棉花根尖原生质体分离的单细胞 RNA-seq 方法；然后，我们使用适合单细胞 RNA-seq 的高效原生质体解离方法，研究了盐胁迫对基因表达谱的影响及其动态变化。在原生质体解离前后，盐处理样品中分别鉴定出 3391 个和 2826 个差异表达基因（DEGs），GO 分析表明这些 DEGs 富集到了包括对刺激的反应、对压力的反应和细胞大分子代谢过程等几个分子组成部分。KEGG 分析表明，植物激素信号转导、苯丙烷生物合成和 MAPK 信号通路富集。在原生质体解离前后，分别有 22 个和 9 个与盐胁迫反应相关的 DEGs 参与植物激素信号和 MAPK 信号通路；有 6 个上调的 DEGs 参与 ABA 信号转导，即 、 、 、 、 ，这表明它们在植物适应盐胁迫方面可能具有潜在的功能。此外，在原生质体解离前后的盐胁迫根中分别有 384 个和 257 个转录因子（TFs）差异表达，其中显著上调的 TFs 主要属于 AP2/ERF-ERF 家族，这表明它们在响应盐胁迫方面可能发挥着重要作用。这些结果不仅为揭示植物根系响应盐胁迫的调控网络提供了新的见解，也为进一步通过单细胞转录组测序探索细胞异质性奠定了坚实的基础。
