Abstract: Lipoxygenase 3(LOX3)is the major component among the LOX isozymes in mature rice seeds.To investigate the role of LOX3 gene under adversity stress,plant expression vector containing antisense of embryo LOX3 cDNA was constructed.Rice varieties Wuyunjing 7 and Kasalath were transformed by Agrobacterium-mediated method and transgenic rice plants were generated.PCR and Southern blot results showed that the antisense LOX3 gene was integrated into the rice genome.The expression of LOX3 gene was suppressed in transgenic plants with antisense gene,which was confirmed by analyzing of embryo LOX3 deletion and semi-quantitive RT-PCR.When T2 transgenic plants were subjected to drought stress and infected with rice blast and bacterial blight,the transgenic plants with the suppression of LOX3 gene were sensitive to drought stress,rice blast and bacterial blight compared with non-transgenic plants.These results suggested that embryo LOX3 gene had some functions in response to adversity stress.

Key words: rice, lipoxygenase 3 gene, antisense RNA, transgenic plants

摘要： LOX3是主要的水稻种胚脂氧合酶同工酶。为了研究水稻LOX3基因在逆境胁迫中的作用，构建了LOX3基因的反义植物表达载体，用农杆菌介导法转化水稻品种武运粳7号和Kasalath，获得了转基因植株。PCR和Southern鉴定证实基因已经导入水稻基因组中，种胚LOX3缺失鉴定和半定量RTPCR分析证实反义RNA抑制了LOX3基因的表达。对T2代转基因植株进行了水分胁迫处理及稻瘟病和白叶枯病的接种鉴定。结果显示，与非转基因对照相比，反义LOX3转基因植株对水分胁迫、稻瘟病和白叶枯病都表现敏感，说明水稻种胚LOX3基因在逆境胁迫反应中发挥一定的作用。

关键词: 水稻, 脂氧合酶基因, 反义RNA, 转基因植株