Interaction of a plant branching architecture affecting fungal effector with the plant E3 ubiquitin ligases RGLG1 and RGLG2

生物营养真菌植物病原菌通过分泌效应物与寄主植物相互作用，效应物是最终进入寄主细胞组织并影响植物基因表达或调节植物蛋白活性的小分泌蛋白。一些效应物已被证明可以改变植物的发育，可能是为了更好地获得真菌定植成功。研究表明，在侵染玉米(Zea Mays cv.)‘Gaspe Flint’)和在拟南芥中稳定表达SAD1的细胞系，其机制尚不清楚。我们已经证明SAD1与玉米和拟南芥的E3泛素连接酶RGLG1和RGLG2相互作用。在这个方案中，我们想要研究SAD1与这些E3泛素连接酶在体外和植物体内的功能相互作用，它在植物组织中的定位和分布，以及RGLG1/2和SAD1的肉豆蔻化对相互作用和亚细胞内分布的可能作用。这将有助于更好地了解效应器如何影响初生植物的发育过程，进而也可能有助于更好地理解决定植物花序分枝结构的因素。

Biotrophic fungal plant pathogens interact with their host plants through the secretion of effectors, small secreted proteins that end up within the host cell tissues and impact plant gene expression or regulation of plant protein activity. A few effectors have been shown to alter plant development possibly for better fungal colonization success. The effector SAD1 of Sporisorium reilianum has been shown to alter plant inflorescence branching architecture both in S. reilianum-infected maize (Zea mays cv. ‘Gaspe Flint’) and in Arabidopsis thaliana lines stably expressing SAD1, by an as yet unknown mechanism. We have shown that SAD1 interacts with the E3 ubiquitin ligases RGLG1 and RGLG2 of both maize and Arabidopsis. In this proposal, we want to characterize the functional interaction of SAD1 with these E3 Ubiquitin ligases, in vitro and in planta, its localization and distribution within the plant tissue, as well as the putative role of myristoylation of both RGLG1/2 and SAD1 for interaction and distribution within subcellular compartments. This will lead to a better understanding of how effectors may impact primary plant developmental processes, which in turn may also lead to a better understanding of the factors determining plant inflorescence branching architecture.