Peptide Signaling in PollenPistil Interactions

Plant fertilization is achieved through the involvement of various pollenpistil interactions. Self-/non-self-recognition in pollination is important to avoid inbreeding, and directional and sustainable control of pollen tube growth is critical for the pollen tube to deliver male germ cells. Recently, various secreted peptides (polypeptides) have been reported to be involved in cellcell communication of pollenpistil interactions. These include determinants of self-incompatibility, factors for pollen germination and tube growth, and pollen tube attractants. Interestingly, many of them are cysteine-rich peptides/polypeptides (CRPs). In this review, I focus on the peptides involved in pollenpistil interactions and discuss properties of peptide signaling in each step from pollination to fertilization.