Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 10, 1999
Publication Date: N/A
Interpretive Summary: The soybean cyst nematode, Heterodera glycines, poses the single greatest disease threat to soybean productivity in the United States. Annual losses to U. S. agriculture due to this microscopic worm approach $2 billion. One problem with current control measures is that they involve resistant soybean cultivars which are often ineffective. New measures which would supplement these controls are urgently needed. Because nematode physiology is an area which offers numerous opportunities for development of safe new control strategies based upon naturally occurring endogenous molecules, this study focuses on identifying nematode proteins critical for proper development of the soybean cyst nematode. In particular, the developing female, which is the main cause of crop damage, was discovered to contain proteins that are essential for reproduction. The results are significant because they represent the first detection of these female- and egg-specific proteins in plant- feeding nematodes. The synthesis of these important molecules by the female provides a target for the development of novel, environmentally sound control agents. This information will be used by biochemists and molecular biologists developing new nematode control options
Technical Abstract: The presence of two major egg proteins was demonstrated in the plant- parasitic nematode, Heterodera glycines. The proteins were present in equal amounts in, and were most abundant in, eggs from yellow females. They were also present in brown females but were absent from juveniles (J2). The two proteins, major egg protein-A (MEP-A) and MEP-B, accounted for more than 50% of the total protein in egg extracts evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis. During development of females from the yellow stage to the brown stage, the levels of MEP-A and MEP-B declined at twice the rate of decline observed in total protein level. MEP-A and MEP-B had molecular weights of 188,000 and 180,000, respectively, similar to those reported for female-specific proteins, vitellins, from free-living nematodes. MEP-A and MEP-B are proposed to be H. glycines vitellins.