Abstract
It is essential for fertilization of angiosperms that a pollen tube grows in a pistil and reaches an embryo sac. There must be various mechanisms that guide pollen tubes to embryo sacs in the fertilization process. However, most of molecules underlying the mechanisms are unclear. Last year, we have identified small, secreted, cysteine-rich polypeptides (CRPs; LURE1, LURE2) as pollen tube attractants derived from the synergid cell of Torenia fournieri.
Our aim of this study is to identify pollen tube attractants of Arabidopsis thaliana that are derived from the synergid cell. As previously suggested by physiological experiments using closely relating species, the candidate genes rapidly evolved, which made difficult to search LUREs homologs in Arabidopsis by conventional molecular phylogenetic analysis. Thus candidates were inveitigated by genome-wide searching used expression data. We performed immunostaining and semi in vitro pollen tube attraction assay for the candidates. Here we report our trial to identify attractants of Arabidopsis, including knock-down analyses to discuss their functions in the pistil.
