FBXO4 Gene: Function, Mutations, and Role in Cancer | NCBI, UniProt

FBXO4 encodes a member of the F-box protein family, which is characterized by an approximately 40-amino acid F-box motif. The protein is a component of the SCF (SKP1-CUL1-F-box protein) ubiquitin ligase complex, which mediates ubiquitination and subsequent proteasomal degradation of target proteins. FBXO4 specifically recognizes and binds to phosphorylated cyclin D1, targeting it for degradation, thereby regulating cell cycle progression. It also interacts with other substrates involved in DNA replication and repair. Loss of FBXO4 function has been implicated in various cancers, including breast, lung, and colorectal cancers.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Ubiquitin mediated proteolysis (KEGG: hsa04120)

• Cell cycle (KEGG: hsa04110)

• SCF complex assembly (Reactome: R-HSA-8951664)

FBXO4 is a 497-amino acid F-box protein that serves as the substrate recognition component of the SCF ubiquitin ligase complex. It contains an N-terminal F-box domain (residues 1-40) that binds SKP1, and a C-terminal substrate-binding domain that recognizes phosphorylated cyclin D1. The protein is predominantly cytoplasmic and regulates G1/S cell cycle transition. Post-translational modifications include phosphorylation, which modulates its stability and activity.