摘   要以拟南芥为实验材料，研究了紫外光诱导拟南芥黄酮生成的最适处理条件，包括UVB的最适光照强度和最适处理时间。鉴定拟南芥突变体的纯合材料，利用PCR技术，筛选出NO,JA,UVR8拟南芥突变体。在紫外光最适处理条件下，研究NO,JA,UVR8对黄酮生成的影响，从而找到介导UVB诱发拟南芥黄酮合成的相关胞内信号分子。85326

实验结果表明：

数据分析：实验结果表明平板培育的18天苗龄的拟南芥，用3 µmol•m-2•s-1强度UVB处理24 h堪非醇K-3RG-7R含量增加最为明显；比对照组约增加两倍，说明该时间该量为最适宜的量。在PCR实验中，采用哥伦比亚野生型拟南芥突变体种子，采用土培法，提取DNA，再进行半定量RT-PCR验证，野生型植株的DNA能扩增出条带，而突变体无法扩增得到条带，表明在该突变体中，UVR8基因不表达，为纯种突变体。UVB处理后拟南芥植株叶片中K-3RG-7R含量明显增加，比对照组约增加1倍；而UVR8突变体植株叶片中K-3RG-7R含量只增加了约10%。这一结果表明UVR8基因突变后，UVB诱发拟南芥黄酮合成受阻，说明UVR是介导UVB诱发拟南芥黄酮合成的必要因子。采用购于种子中心的NO突变体进行以上验证实验，通过NO突变体PCR验证得到野生型植株的cDNA能扩增出条带，而突变体无法扩增得到条带，表明在该突变体中，NO基因不表达，说明NO突变体为纯种突变体。紫外处理后，拟南芥中黄酮K-3RG-7R含量增加十分明显，约为对照的2倍左右；noa1和nia1nia2突变体中K-3RG-7R含量也有所增加，但增加率较拟南芥低，noa1增加率约为对照组的50%，nia1nia2增加率约为20%。以上结果说明NO信号分子参与了UV-B介导拟南芥堪非醇的合成，表明NO信号分子是介导UV-B诱导拟南芥黄酮合成的一个重要元件。JA突变体中AOS1基因不表达，为基因敲除突变体，将其繁殖用于后续实验。由于AOS1突变体不能合成生长所需的JA，所以在开花后需在花芽上每天喷少量终浓度为1 mM的茉莉酮酸甲酯，保证植株能正常结果。

实验结果表明UVB处理后野生型与AOS1突变体中的K-3RG-7R含量均有增加，野生型紫外处理增加率近100%，AOS1中的增加率小于野生型约为70%，说明植株内JA合成可能降低了UVB对K-3RG-7R黄酮合成的诱导作用，但只是抑制了一部分，这表明JA可能参与了UVB诱导拟南芥黄酮合成的过程，但它只是介导UVB诱发黄酮合成，因此JA合成受阻并不能完全抑制UVB对黄酮合成。

Abstract

In this paper, the optimum conditions for the treatment of UVB induced by ultraviolet light in Arabidopsis thaliana were studied。 The Arabidopsis thaliana mutants were identified by using PCR technology, and NO, JA and UVR8 mutants were identified。 The effects of NO, JA and UVR8 on the production of flavonoids were studied under the condition of UV light, so as to find out the related intracellular signal molecules that induce the synthesis of UVB。 

The experimental results show that each stage of plate cultivation of 18 D seedling age of Arabidopsis, with 3 mol - m-2 - S-1 strength UV-B treatment for 24 h, kaempferol content of K-3RG-7R increased significantly; compared with the control group increased by about two times, and repeatedly verified there were identical increasing trend, indicating that the processing conditions can significantly increase the content of K-3RG-7R UV-B, can be regarded as the optimum processing conditions of synthesis induced by K-3RG-7R。 In the PCR experiment, the Columbia wild type Col-0uvr8 and mutant seed extract DNA by soil culture method, then the semi quantitative RT-PCR validation, wild type plants cDNA can amplify bands, but not mutant amplified bands showed that in the mutant, UVR8 gene, gene knockout (knock-out) mutant。 The content of K-3RG-7R in the leaves of Col-0 plants was significantly increased after UV-B treatment, which was about 1 times higher than that of the control group, while the content of K-3RG-7R in the leaves of uvr8 mutant plants increased by only about。 The results indicated that UV-B induced the synthesis of Arabidopsis thaliana was blocked by UVR8, indicating that UVR8 is a necessary factor to induce the synthesis of UV-B in Arabidopsis thaliana。 The NO mutant seeds were purchased from the center of above experiments, the NO mutant Semi-qRT-PCR verified in wild-type plants cDNA can amplify bands, but not mutant amplified bands showed that in the mutant, the expression of NO gene, NO mutant gene knockout mutant。 After UV treatment, the content of flavonoids in K-3RG-7R Col-0 increased obviously, about 2 times as control; noa1 and nia1nia2 mutant K-3RG-7R content also increased, but the increase rate was lower than that of Col-0, noa1 increase rate is about 50% in the control group, the increase of nia1nia2 rate is about 20%。 These results suggest that NO signaling molecules are involved in the UV-B mediated synthesis of UV-B in Arabidopsis, suggesting that NO signaling molecules are an important component of the synthesis of Arabidopsis thaliana。 The AOS1 gene in the JA mutant was not expressed, and it was a knockout mutant。 Since the AOS1 mutant could not synthesize the JA required for growth, it was necessary to spray a small amount of methyl jasmonate at the end of the flower bud to 1 mM per day to ensure the normal results。