Department of Plant Biology and Forest Genetics, Uppsala Biocenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden.
J Exp Bot. 2013 Feb;64(4):935-48. doi: 10.1093/jxb/ers372. Epub 2013 Jan 10.
ML (MD2-related lipid recognition) proteins are known to enhance innate immune responses in mammals. This study reports the analysis of the putative ML gene family in Arabidopsis thaliana and suggests a role for the ML3 gene in herbivory-associated responses in plants. Feeding by larvae of the Lepidopteran generalist herbivore Spodoptera littoralis and larvae of the specialist herbivore Plutella xylostella activated ML3 transcription in leaf tissues. ML3 loss-of-function Arabidopsis plants were compromised in the upregulation of herbivory-induced genes and displayed a semi-dwarf phenotype. Herbivory bioassays showed that larvae of S. littoralis fed on ml3 mutant plants gained more weight compared to larvae fed on wild-type plants while larvae of P. xylostella did not show any significant difference. Virus-induced gene silencing of ML3 expression in plants compromised in jasmonic acid (JA) and salicylic acid (SA) signalling revealed a complex role of ML3 in JA/defence signalling affecting both JA- and SA-dependent responses. The data suggest that ML3 is involved in herbivory-mediated responses in Arabidopsis and that it has a potential role in herbivory-associated molecular pattern recognition.
ML（与 MD2 相关的脂质识别）蛋白已知可增强哺乳动物的先天免疫反应。本研究报告了拟南芥中 ML 基因家族的分析，并提出了 ML3 基因在植物与取食相关的反应中的作用。鳞翅目多食性植食性幼虫如斜纹夜蛾和小菜蛾取食会激活叶片组织中的 ML3 转录。ML3 功能丧失型拟南芥植物在诱导基因的上调中受到损害，并表现出半矮化表型。取食生物测定表明，与取食野生型植株的幼虫相比，斜纹夜蛾幼虫在取食 ml3 突变体植株上获得了更多的体重，而小菜蛾幼虫则没有表现出任何显著差异。在茉莉酸（JA）和水杨酸（SA）信号传导受损的植物中，通过病毒诱导的基因沉默抑制 ML3 表达，揭示了 ML3 在 JA/防御信号传导中的复杂作用，影响了 JA 和 SA 依赖性反应。数据表明，ML3 参与了拟南芥中的取食介导的反应，并且在与取食相关的分子模式识别中具有潜在作用。
