CuO NPs对大豆根尖细胞壁及果胶合成相关基因表达的影响

Effects of CuO NPs on Cell Walls and Pectin Synthesis-related Gene Expression of Soybean Root Tips

以大豆(Glycine max)种子为试验材料,水培生根至2 cm,研究了CuO NPs不同浓度(0、2、5和10 mg/L)处理对大豆根尖细胞壁和果胶成分及果胶合成相关基因的影响。结果表明,CuO NPs对细胞壁和细胞器造成损伤,FTIR红外光谱表明,大豆根细胞壁参与了CuO NPs的防御。通过HPLC结果分析,CuO NPs处理后大豆根细胞壁果胶中的同型半乳糖醛酸聚糖(HG)含量有明显的升高,在5 mg/L CuO NPs处理24 h后为对照的2.09倍。通过转录测序发现大豆根中有58个果胶合成相关候选基因,其中的差异显著基因有15个。进一步对转录组中丰度较高的果胶合成相关的基因进行qRT-PCR分析,发现这些基因的相对表达量均发生变化,GmGATL7在2 mg/L CuO NPs处理24 h时表达上调,GmGATL1、GmGATL3和GmGAUT4在5 mg/L CuO NPs处理24 h时表达上调,GmGAUT12随处理浓度的增加先下调后上调,GmGAUT15在CuO NPs处理后的表达下调,这些基因的表达变化说明果胶在CuO NPs的防御中具有作用。

In this study,soybean(Glycine max)seeds were used as materials.When the roots were about 2 cm,they were seperately treated with different CuO NPs concentrations(0,2,5,10 mg/L).The effects of CuO NPs on cell walls,pectin constituents and pectin synthesis-related genes of soybean roots were studied.The results showed that CuO NPs damaged the cell walls and organelles.FTIR infrared spectroscopy showed that the cell walls were involved in the defense to CuO NPs.Analysis of HPLC data illustrated that after CuO NPs treatment,the contents of homogalacturonic acid(HG)in the pectin in the cell walls increased significantly.When the roots were treated with 5 mg/L CuO NPs for 24 h it was 2.09 times that of the control.Transcriptome analysis revealed that there were 58 pectin synthase-related genes in soybean roots,among which 15 genes were significantly different.Those genes with higher abundance in the transcriptome were analyzed with qRT-PCR technology,which showed that the relative expression of them changed.GmGATL7 was up-regulated when treated with 2 mg/L CuO NPs for 24 h.The expressions of GmGATL1,GmGATL3 and GmGAUT4 were up-regulated when treated with 5 mg/L CuO NPs for 24 h.GmGAUT12 was first down-regulated and then up-regulated with the increase of treatment concentration,and the expressions of GmGAUT15 was down-regulated after CuO NPs treatment.The expression changes of these genes indicate that pectin may play an important role in defense to CuO NPs.