CYFIP1 encodes a protein that regulates cytoskeletal dynamics and protein translation. The encoded protein is a component of the WAVE regulatory complex (WRC), which promotes actin polymerization.This protein also interacts with the Fragile X mental retardation protein (FMRP) and translation initiation factor 4E to inhibit protein translation. A large chromosomal deletion including CYFIP1 is associated with increased risk of schizophrenia and epilepsy in human patients. Reduced expression of this gene has been observed in various human cancers and the encoded protein may inhibit tumor invasion.