Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: 10/15/2005
Publication Date: 1/15/2006
Citation: Giovanini, M.P., Saltzmann, K.D., Ohm, H.W., Williams, C.E. 2006. Up-regulation of a novel wheat lectin-like gene is associated with resistance to Hessian fly larvae. Plant and Animal Genome Conference. Available: http://www.intl-pag.org/14/abstracts/PAG14_P800.html. Interpretive Summary:
Technical Abstract: The incompatible interaction of wheat (Triticum aestivum) plants with Hessian fly (Mayetiola destructor) results in larval death when avirulent larvae attempt to establish a feeding site at the base of wheat seedlings. The resistance response is governed by a gene-for-gene recognition event, which only now is beginning to be understood. We cloned a lectin-like gene, Hfr-3, and determined that the mRNA is highly up-regulated (up to 3000-fold) during the first four days of resistance. The coding region encompasses an ORF of 597 bp and contains no intron. The encoded protein sequence has four chitin binding domains and shares 70% identity with wheat germ agglutinin. Genomic Southern analysis of Hfr-3 revealed that the gene is present in at least one copy on each of the homeologous group 7 chromosomes in hexaploid common wheat. An HFR-3-specific antibody was used in western analysis to evaluate the accumulation of the protein during avirulent larval attack and to verify ingestion by larvae. We propose that the HFR-3 protein acts by targeting chitin present in the peritrophic membranes that line the midgut of the larvae. Binding of HFR-3 to the internal surface of the midgut could interfere with uptake of nutrients contributing to larval death by starvation.