Hiraoka Yukihiro, Ueda Hiroaki, Sugimoto Yukihiro
Graduate School of Agricultural Science, Kobe University, Rokkodai, Nada, 657-8501 Kobe, Japan.
J Exp Bot. 2009;60(2):641-50. doi: 10.1093/jxb/ern316. Epub 2008 Dec 16.
Lotus japonicus genes responsive to parasitism by the compatible species Orobanche aegyptiaca and the incompatible species Striga hermonthica were isolated by using the suppression subtractive hybridization (SSH) strategy. O. aegyptiaca and S. hermonthica parasitism specifically induced the expression of genes involved in jasmonic acid (JA) biosynthesis and phytoalexin biosynthesis, respectively. Nodulation-related genes were almost exclusively found among the Orobanche-induced genes. Temporal gene expression analyses revealed that 19 out of the 48 Orobanche-induced genes and 5 out of the 48 Striga-induced genes were up-regulated at 1 dai. Four genes, including putative trypsin protease inhibitor genes, exhibited systemic up-regulation in the host plant parasitized by O. aegyptiaca. On the other hand, S. hermonthica attachment did not induce systemic gene expression.
利用抑制性消减杂交（SSH）策略，分离出了日本百脉根中对兼容物种埃及列当和不兼容物种独脚金寄生产生响应的基因。埃及列当和独脚金的寄生分别特异性地诱导了参与茉莉酸（JA）生物合成和植保素生物合成的基因表达。结瘤相关基因几乎只在列当诱导的基因中被发现。基因表达的时序分析表明，48个列当诱导基因中有19个以及48个独脚金诱导基因中有5个在寄生后第1天被上调。包括假定的胰蛋白酶蛋白酶抑制剂基因在内的4个基因在被埃及列当寄生的寄主植物中表现出系统性上调。另一方面，独脚金的附着并未诱导系统性基因表达。
