Terras F R, Penninckx I A, Goderis I J, Broekaert W F
F.A. Janssens Laboratory of Genetics, Katholieke Universiteit Leuven, Heverlee-Leuven, Belgium.
Planta. 1998 Sep;206(1):117-24. doi: 10.1007/s004250050381.
Radish leaves contain two homologous 5-kDa plant defensins which accumulate systemically upon infection by fungal pathogens (F.R.G. Terras et al., 1995, Plant Cell 7: 573-588). Here we report on the molecular cloning of the cDNAs encoding the two pathogen-inducible plant defensin isoforms from radish (Raphanus sativus L.) leaves. Tissue-print and whole-leaf electroblot immunostaining showed that the plant defensin peptides not only accumulate at high levels at or immediately around the infection sites in leaves inoculated with Alternaria brassicicola, but also accumulate in healthy tissue further away from the infection sites and in non-infected leaves from injected plants. Gel blot analysis of RNA confirmed that expression of plant defensin genes is systemically triggered upon fungal infection whereas radish PR-1 gene expression is only activated locally. In contrast to the radish PR-1 gene(s), expression of the radish plant defensin genes was not induced by external application of salicylic acid. Activation of the plant defensin genes, but not that of PR-1 genes, occurred upon treatment with methyl jasmonate, ethylene and paraquat.
萝卜叶含有两种同源的5 kDa植物防御素，在受到真菌病原体感染后会在体内积累（F.R.G. 特拉拉斯等人，1995年，《植物细胞》7：573 - 588）。在此，我们报告从萝卜（Raphanus sativus L.）叶中编码两种病原体诱导型植物防御素同工型的cDNA的分子克隆。组织印迹和全叶电印迹免疫染色表明，植物防御素肽不仅在接种链格孢菌的叶片感染部位或其紧邻部位大量积累，而且在远离感染部位的健康组织以及注射植株的未感染叶片中也有积累。RNA的凝胶印迹分析证实，真菌感染会系统性地触发植物防御素基因的表达，而萝卜PR - 1基因的表达仅在局部被激活。与萝卜PR - 1基因不同，萝卜植物防御素基因的表达不会因外源施加水杨酸而被诱导。用茉莉酸甲酯、乙烯和百草枯处理后，植物防御素基因被激活，但PR - 1基因未被激活。
