Hieno Ayaka, Naznin Hushna Ara, Hyakumachi Mitsuro, Higuchi-Takeuchi Mieko, Matsui Minami, Yamamoto Yoshiharu Y
The Graduate School of Agricultural Science, Gifu University.
Microbes Environ. 2016 Jun 25;31(2):154-9. doi: 10.1264/jsme2.ME16025. Epub 2016 Jun 10.
The plant growth-promoting fungus (PGPF), Penicillium simplicissimum GP17-2 (GP17-2), induces systemic resistance against Pseudomonas syringae pv. tomato DC3000 (Pst) in Arabidopsis thaliana. The molecular mechanisms underlying induced systemic resistance (ISR) by GP17-2 were investigated in the present study. Microscopic observations revealed that stomatal reopening by Pst was restricted by elicitation with the culture filtrate (CF) from GP17-2. A gene expression analysis of MYB44, which enhances abscisic acid signaling and consequently closes stomata, revealed that the gene was activated by CF. CF-elicited myb44 mutant plants failed to restrict stomatal reopening and showed lower resistance to Pst than wild-type plants. These results indicate that stomatal resistance by GP17-2 is mediated by the gene activation of MYB44. We herein revealed that the MYB44-mediated prevention of penetration through the stomata is one of the components responsible for GP17-2-elicited ISR.
促进植物生长的真菌（PGPF）简单青霉GP17-2（GP17-2）可诱导拟南芥对丁香假单胞菌番茄致病变种DC3000（Pst）产生系统抗性。本研究对GP17-2诱导系统抗性（ISR）的分子机制进行了研究。显微镜观察显示，Pst引起的气孔重新开放受到GP17-2培养滤液（CF）诱导的限制。对增强脱落酸信号传导并因此关闭气孔的MYB44进行基因表达分析，结果显示该基因被CF激活。CF诱导的myb44突变体植株未能限制气孔重新开放，且对Pst的抗性低于野生型植株。这些结果表明，GP17-2介导的气孔抗性是由MYB44的基因激活介导的。我们在此揭示，MYB44介导的防止通过气孔穿透是GP17-2诱导的ISR的组成部分之一。
