核质转运受体在抗病蛋白的核易位中起关键作用,但相关机制尚不清楚.拟南芥基因SAD2编码输入蛋白β样蛋白。过表达SAD2的转基因拟南芥系(OESAD2/Col-0)对丁香假单胞菌pv表现出明显的抗性。番茄DC3000(PstDC3000)与野生型(Col-0)相比,但基因敲除突变体sad2-5易感.然后在用PstDC3000接种后0、1、2和3天对Col-0、OESAD2/Col-0和sad2-5叶进行转录组学分析。总共1825个差异表达基因(DEG)被鉴定为由SAD2调控的推定生物应激防御基因,其中45个在SAD2敲除和过表达数据集之间重叠。基因本体论(GO)分析表明,DEG广泛参与单生物体细胞代谢过程和对刺激性应激的反应。京都基因和基因组百科全书(KEGG)生化途径分析显示,许多DEGs与类黄酮和其他特殊代谢产物的生物合成有关。转录因子剖析显示,年夜量的ERF/AP2、MYB、和bHLH转录因子参与SAD2介导的植物抗病性。这些结果为今后探索与SAD2介导的抗病相关的分子机制和建立一套关键的候选抗病基因奠定了基础。
Nucleocytoplasmic transport receptors play key roles in the nuclear translocation of disease resistance proteins, but the associated mechanisms remain unclear. The Arabidopsis thaliana gene
SAD2 encodes an importin β-like protein. A transgenic Arabidopsis line overexpressing
SAD2 (OESAD2/Col-0) showed obvious resistance to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) compared to the wild type (Col-0), but the knockout mutant
sad2-5 was susceptible. Transcriptomic analysis was then performed on Col-0, OESAD2/Col-0, and
sad2-5 leaves at 0, 1, 2, and 3 days post-inoculation with Pst DC3000. A total of 1825 differentially expressed genes (DEGs) were identified as putative biotic stress defense genes regulated by SAD2, 45 of which overlapped between the
SAD2 knockout and overexpression datasets. Gene Ontology (GO) analysis indicated that the DEGs were broadly involved in single-organism cellular metabolic processes and in response to stimulatory stress. Kyoto Encyclopedia of Genes and Genomes (KEGG) biochemical pathway analysis revealed that many of the DEGs were associated with the biosynthesis of flavonoids and other specialized metabolites. Transcription factor analysis showed that a large number of ERF/AP2, MYB, and bHLH transcription factors were involved in SAD2-mediated plant disease resistance. These results provide a basis for future exploration of the molecular mechanisms associated with SAD2-mediated disease resistance and establish a set of key candidate disease resistance genes.