F-box only protein 2 is a protein that in humans is encoded by the FBXO2 gene.

This gene encodes a member of the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box. The F-box proteins constitute one of the four subunits of the ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination. The F-box proteins are divided into 3 classes: Fbws containing WD-40 domains, Fbls containing leucine-rich repeats, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbxs class. This protein is highly similar to the rat NFB42 (neural F Box 42 kDa) protein which is enriched in the nervous system and may play a role in maintaining neurons in a postmitotic state. [provided by RefSeq, Jul 2008].