Conlan Brendon, Stoll Thomas, Gorman Jeffrey J, Saur Isabel, Rathjen John P
Research School of Biology, The Australian National University, Acton, ACT, Australia.
QIMR Berghofer Medical Research Institute, Herston, QLD, Australia.
Front Plant Sci. 2018 Dec 18;9:1882. doi: 10.3389/fpls.2018.01882. eCollection 2018.
Plant pathogens secrete effector molecules that suppress the plant immune response to facilitate disease development. AvrPto is a well-studied effector from the phytopathogenic bacterium . Here we utilize an proximity dependent biotin ligase labeling technique (BioID) in combination with AvrPto to identify proximal proteins that are potential immune system components. The labeling technique biotinylated proteins proximal to AvrPto at the plasma-membrane allowing their isolation and identification by mass spectrometry. Five AvrPto proximal plant proteins (APPs) were identified and their effect on plant immune function and growth was examined in leaves. One protein identified, RIN4, is a central immune component previously shown to interact with AvrPto. Two other proteins were identified which form a complex and when silenced significantly reduced growth. The first was a receptor like protein kinase (APK1) which was required for Pto/Prf signaling and the second was Target of Myb1 (TOM1), a membrane associated protein with a phosphatidylinositol 5-phosphate (PtdIns5P) binding motif. We have developed a technology to rapidly determine protein interactions within living plant tissue. It is particularly useful for identifying plant immune system components by defining pathogenic effector protein interactions within their plant hosts.
植物病原体分泌效应分子，抑制植物免疫反应以促进病害发展。AvrPto是一种来自植物致病细菌的经过充分研究的效应子。在这里，我们利用邻近依赖性生物素连接酶标记技术（BioID）结合AvrPto来鉴定作为潜在免疫系统成分的近端蛋白。该标记技术对质膜上AvrPto附近的蛋白进行生物素化，从而可以通过质谱法对其进行分离和鉴定。鉴定出了5种AvrPto近端植物蛋白（APPs），并在叶片中检测了它们对植物免疫功能和生长的影响。鉴定出的一种蛋白RIN4是先前已证明与AvrPto相互作用的核心免疫成分。还鉴定出了另外两种形成复合物的蛋白，当它们被沉默时，会显著降低植物生长。第一种是Pto/Prf信号传导所需的类受体蛋白激酶（APK1），第二种是Myb1靶标（TOM1），一种具有磷脂酰肌醇5-磷酸（PtdIns5P）结合基序的膜相关蛋白。我们开发了一种技术来快速确定活植物组织内的蛋白质相互作用。通过定义致病效应蛋白在其植物宿主内的相互作用，该技术对于鉴定植物免疫系统成分特别有用。
