Isolation and transformation of genes from woody plants that have high ability to clean up air polllutants

该项目的目的是从木本植物中分离基因，如杜鹃花，这些植物具有高度的清除二氧化氮的能力，二氧化氮是一种典型的空气污染物。用蛋白质双向凝胶电泳，发现p_15.6和分子量25- 26 kD的多肽斑点，经二氧化氮熏蒸后，其强度增加4 - 5倍。用气相色谱法测定了这些多肽氨基端约20个氨基酸的序列。同源性分析表明，这些多肽与拟南芥gemin基因的同源性为57-68%。研究了编码该多肽的全长cDNA的克隆。利用差异显示技术，我们发现，在响应于二氧化氮熏蒸的情况下，一些mRNA的强度增加或减少。同源性检索表明，这些DNA与已报道的蛋白质或cDNA没有明显的同源性，提示它们中的一些是新基因，其表达在二氧化氮熏蒸后被诱导或降低。利用基因枪法对拟南芥和榕树进行了转化研究。

This project is aimed at the isolation of genes from woody plants such as Rhododendron mucronatum that have high ability to clean up nitrogen dioxide, a typical air pollutant. Using 2-D gel electrophoresis of proteins, we have found that polypeptide spots of p1 5.6 and MW 25-26kD increased their intensities by four to five times in response to fumigation with nitrogen dioxide. About 20 amino acid sequences at the amino terminals of these polypeptides were determined by vapor phase method. Homology search indicated that these polypeptide had 57-68% identity with so-called gemin from Arabidopsis thaliana. Cloning of the full length of cDNA that encodes this polypeptide was investigated. Using differential display method, we have found that several mRNA from the leaves Rhododendron mucronatum increased or decreased their intensities in response to fumigation with nitrogen dioxide. The DNA sequences of several bands were determined, and homology search indicated these DNAs did not have any distinct homology with reported proteins or cDNAs, suggesting that some of them are novel genes whose expression is induced or decreased upon fumigation with nitrogen dioxide. Transformation of Arabidopsis thaliana and Ficus thunbergii using particle bombardment method has also been investigated.