Lipoxygenase 3 (LOX3) is a major component of the LOX isozymes in mature rice seeds. To investigate the role of LOX3 gene under stresses, a plant expression vector containing antisense cDNA of LOX3 was constructed. Ri...Lipoxygenase 3 (LOX3) is a major component of the LOX isozymes in mature rice seeds. To investigate the role of LOX3 gene under stresses, a plant expression vector containing antisense cDNA of LOX3 was constructed. Rice varieties Wuyunjing 7 and Kasalath were transformed by the 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. Analyses of embryo LOX3 deletion and semi-quantitative RT-PCR confirmed the antisense suppression of LOX3 gene in transgenic plants. The T2 antisense plants of LOX3 were sensitive to drought stress, rice blast and bacterial blight compared with non-transgenic plants. These results suggest that the LOX3 gene might function in response to stresses.展开更多
泛素受体蛋白DSK2(dominant suppressor of KAR2)在植物生长发育和逆境胁迫中发挥重要作用,但其在水稻抗病和渗透胁迫中的作用尚未见报道。本研究发现OsDSK2b受多种逆境的调控,该基因的表达水平在稻瘟病菌侵染和20%PEG-6000处理后显著...泛素受体蛋白DSK2(dominant suppressor of KAR2)在植物生长发育和逆境胁迫中发挥重要作用,但其在水稻抗病和渗透胁迫中的作用尚未见报道。本研究发现OsDSK2b受多种逆境的调控,该基因的表达水平在稻瘟病菌侵染和20%PEG-6000处理后显著降低。时空表达分析表明OsDSK2b基因在三叶期幼苗中的表达水平最高,亚细胞定位结果显示该蛋白定位于细胞质。接种稻瘟病菌(GD08-T13和Guy11)后,敲除植株的病斑面积约为0.05 cm^(2)和0.10~0.13 cm^(2),远小于野生型植株的病斑面积(0.24 cm^(2)和0.31 cm^(2))。敲除OsDSK2b显著增强水稻的叶瘟抗性。而且在病原菌侵染后,敲除植株中病程相关蛋白(PR)基因的表达受到明显诱导。敲除OsDSK2b也显著增强水稻的渗透胁迫抗性,20%PEG-6000模拟渗透胁迫处理后,OsDSK2b敲除植株的存活率为58.3%~74.0%,显著高于野生型植株的存活率(17.0%)。OsDSK2b敲除植株的离子渗透率和植株失水率则显著低于野生型植株。扫描显微镜的结果表明,无论在20%PEG-6000处理前后,敲除OsDSK2b能够促进气孔的闭合,且在20%PEG-6000处理后,这种促进作用会更强。此外,qRT-PCR结果表明,在20%PEG-6000处理后,OsDSK2b敲除植株中DREB基因以及脱落酸(ABA)合成或通路相关基因的表达水平显著高于野生型植株,且敲除植株ko6和ko14的内源ABA含量分别为314.2 ng g^(-1)和344.4 ng g^(-1),显著高于野生型植株的内源ABA含量(206.8 ng g^(-1)),揭示OsDSK2b参与调控渗透胁迫的过程同时涉及ABA依赖和ABA非依赖途径。本研究通过解析OsDSK2b基因在水稻应对生物与非生物胁迫时所发挥的调控作用,为水稻抗性品种的选育提供了新的候选基因。展开更多
基金supported by the grants from the National Basic Research Program of China (Grant No. 2004CB117204 and No. 2006CB100200).
文摘Lipoxygenase 3 (LOX3) is a major component of the LOX isozymes in mature rice seeds. To investigate the role of LOX3 gene under stresses, a plant expression vector containing antisense cDNA of LOX3 was constructed. Rice varieties Wuyunjing 7 and Kasalath were transformed by the 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. Analyses of embryo LOX3 deletion and semi-quantitative RT-PCR confirmed the antisense suppression of LOX3 gene in transgenic plants. The T2 antisense plants of LOX3 were sensitive to drought stress, rice blast and bacterial blight compared with non-transgenic plants. These results suggest that the LOX3 gene might function in response to stresses.
文摘泛素受体蛋白DSK2(dominant suppressor of KAR2)在植物生长发育和逆境胁迫中发挥重要作用,但其在水稻抗病和渗透胁迫中的作用尚未见报道。本研究发现OsDSK2b受多种逆境的调控,该基因的表达水平在稻瘟病菌侵染和20%PEG-6000处理后显著降低。时空表达分析表明OsDSK2b基因在三叶期幼苗中的表达水平最高,亚细胞定位结果显示该蛋白定位于细胞质。接种稻瘟病菌(GD08-T13和Guy11)后,敲除植株的病斑面积约为0.05 cm^(2)和0.10~0.13 cm^(2),远小于野生型植株的病斑面积(0.24 cm^(2)和0.31 cm^(2))。敲除OsDSK2b显著增强水稻的叶瘟抗性。而且在病原菌侵染后,敲除植株中病程相关蛋白(PR)基因的表达受到明显诱导。敲除OsDSK2b也显著增强水稻的渗透胁迫抗性,20%PEG-6000模拟渗透胁迫处理后,OsDSK2b敲除植株的存活率为58.3%~74.0%,显著高于野生型植株的存活率(17.0%)。OsDSK2b敲除植株的离子渗透率和植株失水率则显著低于野生型植株。扫描显微镜的结果表明,无论在20%PEG-6000处理前后,敲除OsDSK2b能够促进气孔的闭合,且在20%PEG-6000处理后,这种促进作用会更强。此外,qRT-PCR结果表明,在20%PEG-6000处理后,OsDSK2b敲除植株中DREB基因以及脱落酸(ABA)合成或通路相关基因的表达水平显著高于野生型植株,且敲除植株ko6和ko14的内源ABA含量分别为314.2 ng g^(-1)和344.4 ng g^(-1),显著高于野生型植株的内源ABA含量(206.8 ng g^(-1)),揭示OsDSK2b参与调控渗透胁迫的过程同时涉及ABA依赖和ABA非依赖途径。本研究通过解析OsDSK2b基因在水稻应对生物与非生物胁迫时所发挥的调控作用,为水稻抗性品种的选育提供了新的候选基因。
