PROTEINS OF THE POLLEN COAT OF BRASSICA-OLERACEA

In higher plants, proteins in the coat of the pollen grain are assumed to play an important role in the interaction between pollen and stigm a upon pollination. A polyclonal antiserum was raised against a mixtur e of these proteins. The antiserum strongly reacted with proteins extr acted from the pollen coat and from whole stamens, whereas there was o nly a faint cross-reactivity to proteins from other tissues. Western b lot analysis and immunolocalisation of pollen before and after rinsing with cyclohexane, a treatment that selectively removes the coat layer , showed that the proteins were exclusively located in the pollen coat . The same proved to hold for pollen coat proteins from other Brassica species. The availability of an antiserum creates the opportunity to identify coat protein encoding sequences in a cDNA library of anthers.