Abstract
Many families of flowering plants have evolved genetically controlled self-incompatibility (SI) systems, which inhibit self-fertilization. SI in Brassica is controlled by a single, highly polymorphic locus called the S-locus. When a stigma and an interacting pollen grain share an identical S-haplotype specificity, the pollen is identified to be incompatible and pollen germination or pollen tube growth is inhibited. SI is thought to be initiated by an interaction between a stigmatic recognition component and a pollen component encoded at the S-locus. In Brassica, the S-locus contains S-receptor kinase (SRK) and S-locus protein 11 (SP11). SRK and SP11 control stigma and pollen S-haplotype specificity, respectively. The binding of SP11 to SRK induces the autophosphorylation of SRK, which is thought to trigger the signaling cascade that results in the rejection of self-pollen. In this study, we examined the change of cytoskelton in papilla cells during the pollination process.
