Membrane proteins involved in pollen-pistil interactions

Self-incompatibility (SI) is a widespread mechanism in angiosperms which pr events self-fertilization. This mechanism relies on cell-cell interactions between pollen and pistil. Among the different SI systems that have been re ported, two have been particularly investigated: the gametophytic system of Solanaceae and the sporophytic system of Brassicaceae. In these two famili es, although the molecular bases of SI response are different, secreted and /or membrane-anchored proteins are required for self-pollen rejection. Inte restingly, these proteins exhibit two functions: recognition and a catalyti c activity. In this review article, we present recent advances which permit a better understanding of how these proteins control the male/female recog nition event associated with the SI response. (C) Societe francaise de bioc himie et biologie moleculaire / Elsevier, Paris.