Wang Jie, Yuan Zhipeng, Li Delin, Cai Minghao, Liang Zhi, Chen Quanquan, Du Xuemei, Wang Jianhua, Gu Riliang, Li Li
Beijing Innovation Center for Crop Seed Technology, Ministry of Agriculture and Rural Affairs, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Science, Haikou 571101, China.
Plants (Basel). 2023 Jul 27;12(15):2793. doi: 10.3390/plants12152793.
Anthocyanin, a kind of flavonoid, plays a crucial role in plant resistance to abiotic stress. Salt stress is a kind of abiotic stress that can damage the growth and development of plant seedlings. However, limited research has been conducted on the involvement of maize seedlings in salt stress resistance via anthocyanin accumulation, and its potential molecular mechanism is still unclear. Therefore, it is of great significance for the normal growth and development of maize seedlings to explore the potential molecular mechanism of anthocyanin improving salt tolerance of seedlings via transcriptome analysis. In this study, we identified two W22 inbred lines (tolerant line pur-W22 and sensitive line bro-W22) exhibiting differential tolerance to salt stress during seedling growth and development but showing no significant differences in seedling characteristics under non-treatment conditions. In order to identify the specific genes involved in seedlings' salt stress response, we generated two recombinant inbred lines (RIL and RIL) by crossing pur-W22 and bro-W22, and then performed transcriptome analysis on seedlings grown under both non-treatment and salt treatment conditions. A total of 6100 and 5710 differentially expressed genes (DEGs) were identified in RIL and RIL seedlings, respectively, under salt-stressed conditions when compared to the non-treated groups. Among these DEGs, 3160 were identified as being present in both RIL and RIL, and these served as commonly stressed EDGs that were mainly enriched in the redox process, the monomer metabolic process, catalytic activity, the plasma membrane, and metabolic process regulation. Furthermore, we detected 1728 specific DEGs in the salt-tolerant RIL line that were not detected in the salt-sensitive RIL line, of which 887 were upregulated and 841 were downregulated. These DEGs are primarily associated with redox processes, biological regulation, and the plasma membrane. Notably, the anthocyanin synthesis related genes in RIL were strongly induced under salt treatment conditions, which was consistented with the salt tolerance phenotype of its seedlings. In summary, the results of the transcriptome analysis not only expanded our understanding of the complex molecular mechanism of anthocyanin in improving the salt tolerance of maize seedlings, but also, the DEGs specifically expressed in the salt-tolerant line (RIL) provided candidate genes for further genetic analysis.
花青素作为一种黄酮类化合物，在植物抵御非生物胁迫中起着关键作用。盐胁迫是一种能够损害植物幼苗生长发育的非生物胁迫。然而，关于玉米幼苗通过花青素积累参与耐盐胁迫的研究有限，其潜在分子机制仍不清楚。因此，通过转录组分析探索花青素提高幼苗耐盐性的潜在分子机制，对玉米幼苗的正常生长发育具有重要意义。在本研究中，我们鉴定出两个W22自交系（耐盐系pur-W22和敏感系bro-W22），它们在幼苗生长发育过程中对盐胁迫表现出不同的耐受性，但在未处理条件下幼苗特征无显著差异。为了鉴定参与幼苗盐胁迫响应的特定基因，我们通过杂交pur-W22和bro-W22产生了两个重组自交系（RIL和RIL），然后对在未处理和盐处理条件下生长的幼苗进行转录组分析。与未处理组相比，在盐胁迫条件下，RIL和RIL幼苗中分别共鉴定出6100个和5710个差异表达基因（DEG）。在这些DEG中，有3160个在RIL和RIL中均存在，这些作为共同受胁迫的EDG，主要富集在氧化还原过程、单体代谢过程、催化活性、质膜和代谢过程调控中。此外，我们在耐盐RIL系中检测到1728个在盐敏感RIL系中未检测到的特异性DEG，其中887个上调，841个下调。这些DEG主要与氧化还原过程、生物调控和质膜相关。值得注意的是，RIL中与花青素合成相关的基因在盐处理条件下被强烈诱导，这与其幼苗的耐盐表型一致。总之，转录组分析结果不仅扩展了我们对花青素提高玉米幼苗耐盐性复杂分子机制的理解，而且耐盐系（RIL）中特异性表达的DEG为进一步的遗传分析提供了候选基因。
