Identification of a monoclonal antibody to abscission tissue that recognises xylose/fucose-containing N-linked oligosaccharides from higher plants.

Monoclonal antibodies raised against extracts of the rachis abscission zone of Sambucus nigra L. were selected for high reactivity towards abscission-zone proteins. One antibody (YZ1/2.23) has been shown to cross-react, by both indirect and competition enzyme-linked immunosorbent assay and by Western blotting, with a number of plant enzymes including horseradish peroxidase, rice α-glucosidase, almond β-glucosidase and the lectins from Phaseolus vulgaris and Erythrina cristagalli.The major N-linked oligosaccharide isolated from horseradish peroxidase has the sequence Manα 3(Manα6)(Xylβ2)Manβ4GlcNAcβ4(Fucα3) GlcNAc. This oligosaccharide was found to be a potent inhibitor of the binding of YZ1/2.23 to the intact glycoprotein. The common determinant is therefore contained within this structure.