SOYBEAN CYST NEMATODES (SCN, HETERODERA GLYCINES) ARE TINY WORMS THAT LIVE IN SOIL AND ATTACK SOYBEAN ROOTS. SCN IS THE MOST-DAMAGING SOYBEAN PEST WORLDWIDE, ESPECIALLY SO IN THE US. WHEN SCN INFECTS ROOTS, IT DISRUPTS CELLULAR SIGNALING PATHWAYS IN THE SYNCYTIUM, WHICH IS A SPECIALIZED FEEDING STRUCTURE INDUCED BY THE NEMATODE TO ENABLE SCN TO SUCK NUTRIENTS FROM SOYBEAN PLANTS AND REPRODUCE. DESPITE THE EXTENSIVE DAMAGE SCN CAUSES, WE KNOW LITTLE ABOUT THE BIOLOGY OF SIGNAL DISRUPTION. GAINING SUCH KNOWLEDGE IS IMPORTANT TO DEFEAT THE NUMBER-ONE ENEMY OF SOYBEAN. OUR RECENT RESEARCH INDICATES THAT CERTAIN SOYBEAN ENZYMES CALLED PROTEIN KINASES MAY HAVE IMPORTANT ROLES IN ENABLING SCN INFECTION. WE CAN LEARN MORE ABOUT THESE PROTEINS BY INACTIVATING THEM, ONE-AT-A-TIME, TO DETERMINE THEIR FUNCTION WITH REGARDS TO RESISTANCE, WHICH IS THE FIRST GOAL OF THE PROJECT. WE NEED TO FIND OUT WHICH PROTEIN KINASES ARE MOST IMPORTANT TO THE SCN FEEDING. IN THE SECOND OBJECTIVE A TECHNOLOGY CALLED YEAST TWO-HYBRID SCREEN WILL ALLOW US TO DETERMINE THE SUBSTRATES FOR EACH CANDIDATE PROTEIN KINASE ENZYME, WHICH WILL ALLOW US TO BETTER UNDERSTAND THE SIGNALING PATHWAY AND TO CUT OFF THE FOOD SUPPLY FOR SCN. THE FINAL OBJECTIVE IS TO GENETICALLY ENGINEER SOYBEAN FOR RESISTANCE. THE ENGINEERED SOYBEAN WILL PRODUCE MORE OF THE KEY INACTIVATED ENZYME WITH THE GOAL OF STARVING SCN, WHICH WILL GIVE THE SOYBEAN RESISTANCE TO THIS PEST. THE GROWTH, REPRODUCTION, AND RESISTANCE OF THE ENGINEERED SOYBEAN PLANTS WILL BE EVALUATED IN THE GREENHOUSE AND FIELD. TO UNDERSTAND SIGNALING, THE LEVEL OF GENE EXPRESSION FOR ALL SOYBEAN GENES WILL BE ANALYZED IN THE ENGINEERED PLANTS. THESE EXPERIMENTS SHOULD LEAD TO THE DISCOVERY OF MORE GENES THAT THE PROTEIN KINASES ARE 'TALKING' TO, WHICH WILL EVENTUALLY HELP TO THE PRODUCTION OF SOYBEAN WITH EVEN MORE RESISTANCE TO SCN. IT IS VITAL FOR US AGRICULTURAL SECURITY TO HAVE SOYBEAN THAT HAS BROAD AND ROBUST RESISTANCE TO PESTS, TO WHICH THIS PROJECT PLAYS AN IMPORTANT ROLE.