中国农业科学 ›› 2005, Vol. 38 ›› Issue (12): 2446-2450 .

• 植物保护 • 上一篇    下一篇

HarpinXoo诱导烟草过敏性细胞死亡的细胞及分子特征

刘爱新,李多川,王金生,董汉松   

  • 收稿日期:2005-05-30 修回日期:1900-01-01 出版日期:2005-12-10 发布日期:2005-12-10

HCD in Tobacco Induced by HarpinXoo Showing Characteristics of PCD

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  • Received:2005-05-30 Revised:1900-01-01 Online:2005-12-10 Published:2005-12-10

摘要: HarpinXoo是水稻白叶枯病菌分泌的蛋白质,用harpinXoo注射烟草后20 h,可表现过敏性细胞死亡(hypersensitive cell death, HCD)。对harpinXoo诱导的烟草叶片用DNA特异染料(DAPI)染色后经荧光显微镜观察发现,烟草细胞在harpinXoo诱导后不同时间表现明显的染色质浓缩;对诱导后的烟草DNA经2%琼脂糖凝胶电泳发现,诱导后12 h烟草DNA开始出现弥散的条带,24 h后弥散的小片段大量增加;定量RT-PCR检测发现,harpinXoo诱导的烟草HCD早期即有标志基因hin1和hsr203J的诱导表达。这些结果表明,harpinXoo诱导的烟草细胞死亡,是植物的一种主动反应,具有细胞编程死亡的重要特征。

关键词: harpinXoo, HCD, 染色质浓缩, DNA片断化, 基因表达

Abstract: The proteinaceous elicitor harpinXoo from pathogenic bacteria Xanthomonas oryzae pv. oryzae was found to elicit lesions reminiscent of the hypersensitive response (HR) in tobacco plants (Nicotiana tobacum L., Xanthi; NC). Tobacco leaves infiltrated with 40 μg·ml-1 harpinXoo exhibited a distinct hypersensitive cell death after 20 hours of infiltration, but micro-HR could be observed at the 8th hour of infiltration by Trypan blue staining. Chromatin condensation and nuclear DNA fragmentation, the features of programmed cell death (PCD), were found in the treated leaves using DAPI staining and agarose gel analysis respectively. These results indicated that tobacco leaves induced by harpinXoo had the properties of PCD. In addition, analysis of the mRNA accumulation of hin1 and hsr203J, two marker genes of HCD, indicated a correlation between genes expression and tobacco cell death induced by harpinXoo。

Key words: harpinXoo, HCD, chromatin condensation, DNA fragmentation, gene expression