Mediates with IER2 FGF-signaling in Kupffer's vesicle ciliogenesis and in the establishment of laterality in the embryo (PubMed:19164561). May be involved in mitogenic function of FGF1 (By similarity). Interacts with IER2. Expressed ubiquitously. Morpholino knockdown of the protein causes severe deficits in laterality (PubMed:19164561). Partial loss of Kupffer's vesicle cilia with the length of the remaining cilia reduced (PubMed:19164561). Double morpholino knockdown of IER2 and FIBPB causes an almost complete loss of Kupffer's vesicle cilia (PubMed:19164561).