Characterizing the dynamic changes in the subcellular localization of Rhg1 gene products during SCN infection
J. SMITH (1), A. Bayless (1), J. Song (1), A. Teillet (1), A. Bent (1) (1) University of Wisconsin-Madison, U.S.A.

Soybean (Glycine max) is the world’s most widely used legume crop. Soybean cyst nematode (SCN; Heterodera glycines) is the most economically damaging pathogen of soybean. SCN modifies targeted host root cells to cause the formation of a hypermetabolic feeding cell termed a syncytium. The Rhg1 (Resistance to H. glycines) quantitative trait locus of soybean makes the strongest known contribution to resistance against SCN, by disrupting the formation of syncitia. We recently discovered that Rhg1 is a 31 kb segment of DNA that contains four open reading frames, with the entire segment displaying dramatic copy number variation. Three distinct genes within the 31 kb repeat were each shown to contribute to SCN resistance including a predicted amino acid permease (Glyma18g02580), a predicted α-SNAP protein (mediator of vesicular trafficking; Glyma18g02590), and a protein lacking a predicted function (Glyma18g02610). As one step toward understanding how three dissimilar Rhg1 gene products confer resistance to SCN, we raised and validated antibodies specific for these Rhg1 gene products. We have then used subcellular fractionation, transmission electron microscopy immunolocalization and other methods to characterize the subcellular location and abundance of each Rhg1 gene product during SCN infection, in both SCN-resistant and SCN-susceptible soybean. This has allowed formulation of hypotheses that partially explain the mode of action of this important Rhg1-mediated resistance.

Abstract Number: P17-614
Session Type: Poster