Zhu Yongxing, Ren Ying, Liu Ji'an, Liang Wenguang, Zhang Yuanyuan, Shen Fengyuan, Ling Jiang, Zhang Chunyi
Biotechnology Research Institute, Chinese Academy of Agricultural Science, Beijing 100081, China.
Agricultural Biotechnology Center, Ningxia Academy of Agriculture and Forestry Sciences, Yinchuan 750002, China.
Plants (Basel). 2023 Mar 15;12(6):1331. doi: 10.3390/plants12061331.
(1) Background: Salt stress is an abiotic factor that limits maize yield and quality. A highly salt-tolerance inbred AS5 and a salt-sensitive inbred NX420 collected from Ningxia Province, China, were used to identify new genes for modulating salt resistance in maize. (2) Methods: To understand the different molecular bases of salt tolerance in AS5 and NX420, we performed BSA-seq using an F2 population for two extreme bulks derived from the cross between AS5 and NX420. Transcriptomic analysis was also conducted for AS5 and NX420 at the seedling stage after treatment with 150 mM of NaCl for 14 days. (3) Results: AS5 had a higher biomass and lower Na content than NX420 in the seedling stage after treatment with 150 mM NaCl for 14 days. One hundred and six candidate regions for salt tolerance were mapped on all of the chromosomes through BSA-seq using F2 in an extreme population. Based on the polymorphisms identified between both parents, we detected 77 genes. A large number of differentially expressed genes (DEGs) at the seedling stage under salt stress between these two inbred lines were detected using transcriptome sequencing. GO analysis indicated that 925 and 686 genes were significantly enriched in the integral component of the membrane of AS5 and NX420, respectively. Among these results, two and four DEGs were identified as overlapping in these two inbred lines using BSA-seq and transcriptomic analysis, respectively. Two genes ( and ) were detected in both AS5 and NX420; the transcription level of was induced to be significantly higher in AS5 than in NX420 (41.99 times versus 6.06 times after 150 mM of NaCl treatment for 48 h), while the expression of showed no significant difference upon salt treatment in both lines. The functional annotation of the new candidate genes showed that it was an unknown function protein. (4) Conclusions: is a new functional gene responding to salt stress in the seedling stage, which provides an important genetic resource for salt-tolerant maize breeding.
（1）背景：盐胁迫是限制玉米产量和品质的非生物因素。本研究利用从中国宁夏收集的高度耐盐自交系AS5和盐敏感自交系NX420，鉴定调控玉米耐盐性的新基因。（2）方法：为了解AS5和NX420耐盐性的不同分子基础，我们使用AS5和NX420杂交产生的F2群体构建两个极端混池进行BSA-seq分析。同时，对用150 mM NaCl处理14天的AS5和NX420幼苗进行转录组分析。（3）结果：用150 mM NaCl处理14天后，AS5在幼苗期的生物量高于NX420，Na含量低于NX420。通过对极端群体F2进行BSA-seq分析，在所有染色体上定位了106个耐盐候选区域。基于双亲间的多态性，我们检测到77个基因。利用转录组测序检测到这两个自交系在盐胁迫下幼苗期大量差异表达基因（DEGs）。GO分析表明，分别有925个和686个基因在AS5和NX420的膜整合成分中显著富集。在这些结果中，分别通过BSA-seq和转录组分析在这两个自交系中鉴定出2个和4个重叠的DEGs。在AS5和NX420中均检测到两个基因（和）；在150 mM NaCl处理48小时后，AS5中基因的转录水平诱导显著高于NX420（分别为41.99倍和6.06倍），而在两个品系中，盐处理后基因的表达均无显著差异。新候选基因的功能注释表明它是一个功能未知的蛋白。（4）结论：是一个响应幼苗期盐胁迫的新功能基因，为耐盐玉米育种提供了重要的遗传资源。
