College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China.
Nanchong Academy of Agricultural Sciences, Nanchong 637002, China.
Int J Mol Sci. 2023 Feb 13;24(4):3738. doi: 10.3390/ijms24043738.
In recent times, the excessive accumulation of nitrate has been one of the main reasons for the secondary salinization of greenhouse soils. Light plays a key role in a plant's growth, development, and response to stress. A low-red to far-red (R:FR) light ratio could enhance plant salinity tolerance, but the mechanism at a molecular level is unclear. Thus, we analyzed the transcriptome responses of tomato seedlings to calcium nitrate stress under either a low R:FR ratio (0.7) or normal light conditions. Under calcium nitrate stress, a low R:FR ratio enhanced both the antioxidant defense system and the rapid physiological accumulation of proline in tomato leaves, which promoted plant adaptability. Using weighted gene co-expression network analysis (WGCNA), three modules including 368 differentially expressed genes (DEGs) were determined to be significantly associated with these plant traits. Functional annotations showed that the responses of these DEGs to a low R:FR ratio under excessive nitrate stress were enriched in the areas of hormone signal transduction, amino acid biosynthesis, sulfide metabolism, and oxidoreductase activity. Furthermore, we identified important novel hub genes encoding certain proteins, including FBNs, SULTRs, and GATA-like transcription factor, which may play a vital role in low R:FR light-induced salt responses. These findings offer a new perspective on the mechanisms and environmental implications behind low R:FR ratio light-modulated tomato saline tolerance.
近年来，硝酸盐的过度积累是温室土壤次生盐渍化的主要原因之一。光在植物的生长、发育和对胁迫的反应中起着关键作用。低红到远红（R:FR）光比值可以增强植物的耐盐性，但在分子水平上的机制尚不清楚。因此，我们分析了番茄幼苗在低 R:FR 比值（0.7）或正常光照条件下对硝酸钙胁迫的转录组反应。在硝酸钙胁迫下，低 R:FR 比值增强了番茄叶片中的抗氧化防御系统和脯氨酸的快速生理积累，从而促进了植物的适应性。利用加权基因共表达网络分析（WGCNA），确定了三个包含 368 个差异表达基因（DEGs）的模块与这些植物特性显著相关。功能注释表明，这些 DEGs 对过量硝酸盐胁迫下低 R:FR 比值的反应富集在激素信号转导、氨基酸生物合成、硫化物代谢和氧化还原酶活性等区域。此外，我们鉴定了重要的新枢纽基因，它们编码某些蛋白质，包括 FBNs、SULTRs 和 GATA 样转录因子，这些基因可能在低 R:FR 光诱导的盐响应中发挥重要作用。这些发现为低 R:FR 比值光调节番茄耐盐性的机制和环境影响提供了新的视角。
