The responses of sulfur(S) uptake assimilation-related genes' expression in roots of two rice cultivars to cadmium(Cd), bensulfuron-methyl(BSM) and their co-contamination(Cd+BSM) were investigated by gene-chip microarray analysis and quantitative real-time PCR(QRT-PCR) technology. Treatments of Cd and Cd+BSM induced expression of sulfate transporter and permease genes, and promoted sulfate uptake in rice roots. Cd+BSM could alleviate Cd toxicity to cv. Fengmeizhan seedlings, probably due to Cd+BSM promoting greater S absorption by seedlings. Cd and Cd+BSM induced expression of sulfate assimilation-related genes, and thus activated the sulfur assimilation pathway. Cd and Cd+BSM induced expression of phytochelatin synthase and metallothionein genes, and induced expression of glutathione S-transferases(GSTs), glutathione synthase(GS) and antioxidation enzyme genes, which detoxified Cd2+. It is suggested that(to cope with the toxicity of Cd, BSM and their co-contamination) the S uptake and assimilation pathway was activated in rice roots by increased expression of related genes, thus enhancing the supply of organic S for synthesis of Cd or BSM resistance-related substances.
Jian ZhouZegang WangZhiwei HuangChao LuZhuo HanJianfeng ZhangHuimin JiangCailin GeJuncheng Yang
