LAUSR

ABSTRACT The defense regulon has been defined genetically in Arabidopsis thaliana to involve the syntaxin PENETRATION1 (PEN1), the secreted glucosidase (PEN2) and an ATP-binding cassette (ABC) transporter (PEN3). Experiments in Glycine max (soybean) have identified homologous genes being expressed in root cells undergoing defense processes to Heterodera glycines 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 H. glycines 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 G. max has toward H. glycines parasitism.