Necessary for signaling by class 3 semaphorins and subsequent remodeling of the cytoskeleton. Plays a role in axon guidance, neuronal growth cone collapse and cell migration (By similarity). Homotetramer, and heterotetramer with CRMP1, DPYSL2, DPYSL3 or DPYSL5. Interacts with PLEXA1 (By similarity). Interacts with FLNA (By similarity). Expressed transiently in developing spinal cord and selectively in the postnatal cerebellum. Belongs to the metallo-dependent hydrolases superfamily. Hydantoinase/dihydropyrimidinase family. Lacks most of the conserved residues that are essential for binding the metal cofactor and hence for dihydropyrimidinase activity. Its enzyme activity is therefore unsure.