Component of the FER-regulated Rho GTPase signaling complex. Acts as a chaperone and coreceptor for FER. Required for localization of FER to the plasma membrane. Interacts with FER. Expressed in pollen, pollen tubes, sporophytic pistil tissues, in the early stages of female gametophyte development, and in unfertilized, mature ovules (PubMed:20163554). Expressed in roots, lateral roots, shoots, cotyledons, petioles, developing leaves and anther filaments. Retarded growth, collapsed root hairs, defective trichomes, abnormal accumulation of high levels of anthocyanin and overall reduced plant size (PubMed:26052747). No aborted seed phenotype and normal production of seed sets (PubMed:20163554, PubMed:26052747).