Immuno-gold localization of α-L-arabinofuranosyl residues in pollen tubes of Nicotiana alata Link et otto.

Immuno-gold labelling using a monoclonal antibody (PCBC3) with a primary specificity for α-L-arabinofuranosyl residues was used to locate these residues in pollen tubes of Nicotiana alata grown in vivo. The antibody bound to the outer fibrillar layer of the pollen-tube wall: the inner, non-fibrillar wall layer was not labelled. Cytoplasmic vesicles (0.2 μm diameter) were also labelled. The antibody may bind to an arabinan in the pollen-tube wall.