Production and characterization of the Brassica oleracea self-incompatibility locus glycoprotein and receptor kinase in a baculovirus infected insectcell culture system

Self-incompatibility is a phenomenon that involves recognition of self vers us non-self pollen, leading to the rejection of self-related pollen and pre venting self-fertilization. In this study, we used a baculovirus-infected i nsect cell culture system to express two Brassica oleracea stigma-specific proteins required for self-incompatibility: the S-locus glycoprotein, a sol uble cell wall-localized glycosylated protein, and the S-locus receptor kin ase, a receptor-like integral plasma membrane glycoprotein with serine/thre onine kinase activity. Insect cells expressing the S-locus receptor kinase were used in conjunction with immunofluorescence and a whole cell enzyme-li nked immunosorbant assay to demonstrate that the receptor is targeted to th e cell surface and is oriented with its N-terminal S domain towards the out side of the cell.