Self-Incompatibility in the Brassicaceae

Abstract

Flowering plants have evolved several mechanisms for controlling pollination. Genetic self-incompatibility is one of the most elaborate and ‘smart’ systems known to date. In the Brassicaceae, recognition of ‘self’ pollen in the self-incompatibility response is based on highly specific interactions between matched stigma surface receptors and pollen coat ligands encoded by haplotypes of the S locus, which trigger arrest of pollen tube development. This chapter presents a brief historical account of the analysis of SI in the Brassicaceae, an overview of our current understanding of the recognition and response phases of SI, and a summary of progress made in elucidating the genetic basis of loss of SI and switches to self-fertility in various lineages, with an emphasis on knowledge gained from analysis of a recently- developed transgenic Arabidopsis thaliana self-incompatible model.