Plant self-incompatibility systems: a molecular evolutionary perspective.
Incompatibility recognition systems preventing self-fertilization have evolved several times in independent lineages of Angiosperm plants, and three main model systems are well characterized at the molecular level [the gametophytic self-incompatibility (SI) systems of Solanaceae, Rosaceae and Anthirrhinum, the very different system of poppy, and the system in Brassicaceae with sporophytic control of pollen SI reactions]. In two of these systems, the genes encoding both components of pollen-pistil recognition are now known, showing clearly that these two proteins are distinct, that is, SI is a lock-and-key mechanism. Here, we review recent findings in the three well-studied systems in the light of these results and analyse their implications for understanding polymorphism and coevolution of the two SI genes, in the context of a tightly linked genome region.
Charlesworth
Deborah
D
Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Ashworth Laboratory, King's Buildings, Edinburgh EH9 3JT, UK. deborah.charlesworth@ed.ac.uk
Vekemans
Xavier
X
Castric
Vincent
V
Glémin
Sylvain
S
D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D019143:Evolution, Molecular; D018745:Genome, Plant; D010944:Plants / Q000235:genetics*; D011110:Polymorphism, Genetic; D012098:Reproduction / Q000235:genetics