Korean Ginseng Center for Most Valuable Products and Ginseng Genetic Resource Bank, Kyung Hee University, Suwon, 449-701, South Korea.
Mol Biol Rep. 2011 Apr;38(4):2761-9. doi: 10.1007/s11033-010-0421-7. Epub 2010 Nov 18.
The regulation of reactive oxygen scavengers against biotic and abiotic conditions were investigated in the seedling of Panax ginseng C. A. Meyer. From the EST library we selected the antioxidant marker genes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione peroxidase (GPX), and glutathione synthase (GS). The abiotic chilling, heat, osmotic, oxidative, and wounding stresses and biotic stresses with fungal pathogens were tested against 3-week-grown seedlings. The expression patterns of the genes were analyzed by means of real-time quantitative RT-PCR. The transcriptome result under abiotic stresses showed differential expression and elevated up-regulation of PgSOD, PgGPX, PgGS, and PgAPX, thus it may prove the generation of ROS in ginseng. Whereas, in biotic stress the up-regulation of transcript level merely based on the incompatible interactions. But PgAPX and PgCAT showed no significant change or slight down-regulation of transcript level during pathogen interaction. Thus it may suggest that in ginseng, plant-pathogen interaction triggers defense-related gene transcription via salicylic acid mediated signaling mechanism, and also possess crosstalk signaling networks between abiotic and biotic stress responses.
我们从 EST 文库中筛选了抗氧化标记基因，如超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）、谷胱甘肽过氧化物酶（GPX）和谷胱甘肽合酶（GS），研究了人参幼苗对生物和非生物条件下活性氧清除剂的调节。对 3 周龄幼苗进行了非生物胁迫（冷、热、渗透、氧化和创伤胁迫）和生物胁迫（真菌病原体）测试。通过实时定量 RT-PCR 分析基因的表达模式。非生物胁迫下的转录组结果显示，PgSOD、PgGPX、PgGS 和 PgAPX 的表达出现差异，并上调表达，因此可能证明人参中产生了 ROS。然而，在生物胁迫下，仅基于不亲和相互作用的转录水平上调。但是，在病原体相互作用过程中，PgAPX 和 PgCAT 的转录水平没有明显变化或略有下调。因此，这可能表明，在人参中，植物-病原体相互作用通过水杨酸介导的信号转导机制触发防御相关基因转录，并且还存在非生物和生物胁迫反应之间的交叉信号网络。
