壳寡糖对烟草悬浮细胞茉莉酸合成基因转录的影响  

Effects of Oligochitosan on Transcription of Genes Involved in Jasmonic Acid Biosynthesis in Tobacco Suspension Cells

作　　者：王文霞[1,2] 李曙光[1] 赵小明[1] 林炳承[1] 杜昱光[1] 

机构地区：[1]中国科学院大连化学物理研究所,大连116023 [2]中国科学院研究生院,北京100049

出　　处：《植物学通报》2008年第5期526-532,共7页Chinese Bulletin of Botany

基　　金：中国科学院知识创新工程重要方向项目(No.KSCX2-YW-N-007);863计划(No.2006AA10A213和No.2007AA091600)

摘　　要：采用RT-PCR方法研究了不同浓度壳寡糖对烟草悬浮细胞茉莉酸合成酶基因的转录调控。结果表明,50μg.mL-1壳寡糖能够明显诱导烟草悬浮细胞茉莉酸合成途径的关键酶——磷脂酶A2、13-脂氧合酶、丙二烯氧化物合成酶、丙二烯氧化物环化酶和12-氧-植物二烯酸还原酶基因的表达,而且该浓度的壳寡糖对这些基因的诱导作用相同(似)。在实验设定时间内均诱导表达编码磷脂酶A2的基因,对其它基因的诱导时间均为8小时,表明50μg.mL-1壳寡糖在诱抗过程中启动了茉莉酸合成途径。而200μg.mL-1壳寡糖的处理对这些基因的表达无显著影响。表明不同浓度的壳寡糖对烟草悬浮细胞的作用模式存在差异,且高浓度的壳寡糖在烟草悬浮细胞中启动的信号通路可能没有茉莉酸信号的参与。Oligochitosan prepared by enzymatic hydrolysis of chitosan is a potent plant defense elicitor, but the mechanism of oligochitosan inducing resistance of plants to pathogens is still unclear. In this study, we applied different concentrations of oligochitosan to tobacco suspension cells to investigate the change in gene expression involved in jasmonic acid biosynthesis. Semi-quantitative RT-PCR revealed that 50 μg·mL^-1 oligochitosan up-regulated the expression of genes encoding phospholipase A2, 13-1ipoxygenase, allene oxide synthase, allene oxide cyclase and 12-oxo-phytodienoic acid reductase in a similar manner. The gene expression of phospholipase A2 was increased over time, whereas increased expression of the other genes appeared at 8 h after treatment. These results showed that the jasmonic acid biosynthesis pathway can be triggered by 50 μg·mL^-1, rather than 200 μg·mL^-1, oligochisan suggesting that the action of oligochitosan in tobacco suspension cells was dose dependent, and that a higher concentration of oligochitosan may activate a defense response without the participation of jasmonic acid.

关 键 词：诱导抗病性 茉莉酸 壳寡糖 烟草悬浮细胞 

分 类 号：Q943[生物学—植物学]