Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/5/2005
Publication Date: 9/3/2005
Citation: Kovaleva, E.S., Masler, E.P., Subbotin, S.A., Chitwood, D.J. 2005. Molecular Characterization of Aldolase from Heterodera glycines and Globodera Rostochiensis. Journal of Nematology. 37:292-296. Interpretive Summary: Plant-parasitic nematodes are microscopic worms that cause billions of dollars in crop losses in the United States. Two of the most important plant-parasitic nematodes are the cyst nematodes that attack potatoes and soybeans. Farmers in the United States face an increasing need for affordable, effective, and environmentally acceptable control agents to combat these pests. A key place to look for new targets for control is within the nematode itself. We report here the discovery of one such target in cyst nematodes called the aldolase gene. Aldolase is used by nematodes to convert food into the energy they need for development, reproduction and overall survival. This discovery is important because it is the first report of this gene for any plant-parasitic nematode, and the importance of the aldolase gene makes it a prime natural target at which to focus development of a variety of natural control strategies. This information will be used by researchers in the agrochemical and agricultural biotechnology industries who are developing safe, selective and cutting-edge methods for nematode control.
Technical Abstract: Fructose-biphosphate aldolase (E. C. 18.104.22.168) is a key enzyme in glycolysis. We have characterized full-length coding sequences for aldolase from the cyst nematodes Heterodera glycines and Globodera rostochiensis, the first for any plant-parasitic nematode. Nucleotide homology is very high (83% identity) and the respective sequences encode 40kDa proteins with 89% amino acid identity. Genomic sequences contain 6 introns located at identical positions in both genes. Intron 4 in H. glycines is unusually large. Partial genomic sequences from seven additional cyst nematode species reveal that the large fourth intron is characteristic of the Heterodera but not Globodera aldolase genes. Total aldolase-like activity in homogenates from different developmental stages of H. glycines and from two free-living nematodes, Caenorhbditis elegans and Panagrellus redivivus, was quantified. Activity in H. glycines was highest in J2, and activities in the free-living species were 2-fold higher than in H. glycines. The Heterodera glycines J2 aldolase has Km = 41 micromolar and is inhibited by treatment with carboxypeptidase A or sodium borohydride.