Fertilization relies on complex and specialized mechanisms that achieve the precise delivery of the male gamete to the female gamete and their subsequent union. In plants, the molecular mechanisms that mediate the discharge of sperm cells by the male gametophyte (pollen tube) into the female gametophyte are still a mystery although they are of great interest for the manipulation of breeding barriers in wide-crosses and the production of hybrids. Recently, it was shown that a molecular dialogue between the male and female gametophytes must occur for successful sperm discharge. A receptor-like kinase called FERONIA has been shown by U. Grossniklaus’s group (UZH, Switzerland), the Host Laboratory, to be required for this dialogue in the female gametophyte. The French Research Fellow Aurélien Boisson-Dernier initiated this project in his former laboratory (J. Schroeder’s group, UCSD, USA) and recently (November 16th 2008) joined U. Grossniklaus’s group to characterize PFERL-RLKs (pollen-expressed FERONIA-like receptor-like kinases), which are excellent candidates to assume the role of the FER counterpart in the male gametophyte. The project and the Research Fellow’s career will greatly benefit from the training and expertise offered by the Host Lab, as well as from its on-going in-depth characterization of FER-dependent signaling. This highly interdisciplinary proposal that includes molecular and cell biological, cytological, genetic, biochemical, and interactome approaches should result in the identification of the first components of the FER signaling counterpart in the pollen tube, essential for male-female gametophytic interactions and fertilization. Consequently, this project will allow the Research Fellow to establish himself as an independent leading scientist in Europe exploiting (i) this novel niche in the plant fertilization field, (ii) the new skills he will acquired in the Host Lab, and (iii) the scientific network he will develop during at the Host Lab.