中文摘要：

硫化氢（H2S）信号参与植物对多种生物和非生物胁迫的响应．拟南芥中H2S产生酶包括L-半胱氯酸脱巯基酶（LCD），D-半胱氧酸脱巯基酶（DCD1，DCD2），脱巯基酶（DES），固氮酶（NFS1，NFS2）．分析以上各酶基因的启动子区域，结果显示其都含有WRKY转录因子结合位点W-box．凝胶阻滞实验结果表明：WRKY18和WRKY60结合LCD，DCD1，DCD2，DES和NFS2启动子；WRKY40结合NFS1启动子实时荧光定量PCR结果表明：在WRKY18，WRKY40和WRKY604相关突变体中LCD，DES和DCD1基因表达上调；DCD2表达下调．镉（Cd）胁迫后，WRKY18，WRKY40和WRKY6D的双突变体和三突变体的H2S产率高于单突变体和野生型，且在含Cd^2＋的1／2MS培养基上表现比野生型和单突变体抗Cd．以上结果表明WRKY转录因子通过调节H2S信号参与植物对Cd胁迫的响应．

英文摘要：

Hydrogen sulfide （H2S） is a gasotransmitter playing a vital role in response to biotic and abiotic stress for plants. In order to understand the transcriptional regulation of the genes that are responsible for endogenous H2S generation, the promoter sequences of L-cysteine desulfhydrase （LCD）, D-cysteine desulfhydrase （DCD1, DCD2）, desulfhydrase （DES） and nitrogen fixation synthetase （NFS1, NFS2） were analyzed. They are all found to contain a W-box, a characteristic core binding site for the plant WRKY transcription factors, which have important roles in the plant＇s responses to numerous stresses by modifying the expression patterns of their target genes. An electrophoretic mobility shift assay indicated that WRKY 18 and WRKY60 interacted with the W-box in the promoters of the LCD, DCD1, DCD2, DES and NFS2 genes, whereas WRKY40 bound to the W-box of the NFS1 promoter. The expression levels of the LCD, DES and DCD1 genes were up-regulated, but the DCD2 was downregulated in the plants with WRKY18, WRKY40 or WRKY60 mutations. The plants with double and triple mutations of WRKY18, WRKY40 and WRKY60 had a higher rate of H2S production during cadmium stress and were more resistant to the cadmium stress than the wild type or single mutants. These results suggest that WRKY transcription factors regulate the H2S signaling pathway in plants, allowing them to cope with cadmium stress.