SELF-INCOMPATIBILITY RELATED GLYCOPROTEINS OF BRASSICA ARE PRODUCED AND SECRETED BY TRANSGENIC TOBACCO CELL-CULTURES

A Nicotiana tabacum cell line was transformed, using particle bombardm ent, with constructs encoding the Brassica stigma glycoproteins, S-loc us glycoprotein(SLG)-6 and S-locus related glycoprotein-1, under the c ontrol of a duplicated cauliflower mosaic virus 35S promoter and the n os terminator sequence. Calli and cell suspension lines that express e ach of the two proteins were recovered. Using specific antibodies, the foreign proteins can be detected in the cells, the cell wall eluate a nd the culture medium. The characteristic band patterns representing g lycoforms (and isoforms) of the transgenically produced proteins on so dium dodecyl sulfate and isoelectric focusing protein gels are very si milar to those from Brassica stigmas. Partial purification of SLG from the culture medium is described and the potential of the system for s tudying the biochemical basis of self-incompatibility is discussed.