An expanded role of the SNARE-containing regulon as it relates to the defense process that <i>Glycine max</i> has to <i>Heterodera glycines</i>

The defense regulon has been defined genetically in <i>Arabidopsis thaliana</i> to involve the syntaxin <i>PENETRATION1</i> (<i>PEN1</i>), the secreted glucosidase (<i>PEN2</i>) and an ATP-binding cassette (ABC) transporter (<i>PEN3</i>). Experiments in <i>Glycine max</i> (soybean) have identified homologous genes being expressed in root cells undergoing defense processes to <i>Heterodera glycines</i> parasitism. These experiments have not examined proteins involved in cargo delivery to the infection site. A good candidate fulfilling this role would be myosin XI. In related studies, prior microscopic analyses have shown the accumulation of callose at these defense sites. Experiments presented here show that callose synthase expression impairs <i>H. glycines</i> parasitism. The experiments presented here have expanded on prior results demonstrating the central defense role of the plant vesicular trafficking apparatus and callose synthase to the defense process that <i>G. max</i> has toward <i>H. glycines</i> parasitism.

在拟南芥（Arabidopsis thaliana）中，防御调节子（defense regulon）通过遗传学手段得以定义，其组分包含突触融合蛋白（syntaxin）PENETRATION1（PEN1）、分泌型葡糖苷酶（secreted glucosidase）PEN2以及ATP结合盒（ATP-binding cassette, ABC）转运蛋白PEN3。针对大豆（Glycine max）的相关实验已鉴定出：在应对大豆胞囊线虫（Heterodera glycines）寄生的防御过程中，其根系细胞内会表达对应的同源基因。但上述实验未考察参与向侵染位点递送货物（cargo）的相关蛋白。满足该功能的优质候选蛋白为肌球蛋白XI（myosin XI）。在相关研究中，既往显微分析已证实，此类防御位点会发生胼胝质（callose）积累。本研究的实验结果表明，胼胝质合酶（callose synthase）的表达会抑制大豆胞囊线虫的寄生过程。本研究的实验进一步拓展了既往结论，证实了植物囊泡转运装置（vesicular trafficking apparatus）与胼胝质合酶在大豆应对大豆胞囊线虫寄生的防御过程中发挥核心防御作用。