FBXO21
F-box protein 21: a component of the SCF ubiquitin ligase complex involved in cell cycle regulation and protein degradation
Gene Information Card
| Symbol | FBXO21 |
|---|---|
| Full Name | F-box protein 21 |
| Gene Type | protein-coding |
| Chromosomal Location | 12q24.21 |
| NCBI Gene ID | 23014 ncbi.nlm.nih.gov/gene/23014 |
| Ensembl ID | ENSG00000111247 |
| UniProt ID | O94952 |
| OMIM ID | 609095 |
| HGNC ID | 13586 |
| Aliases | FBX21, F-box only protein 21 |
Description
FBXO21 encodes a member of the F-box protein family, which is characterized by an F-box domain. F-box proteins are components of the SCF (SKP1-CUL1-F-box protein) ubiquitin ligase complex, which mediates ubiquitination and subsequent proteasomal degradation of target proteins. FBXO21 specifically recognizes and binds phosphorylated substrates, playing a role in cell cycle progression, signal transduction, and protein turnover. It is widely expressed in various tissues and has been implicated in cancer and other diseases.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Cancer (various types) | Dysregulation of FBXO21 may alter ubiquitination of cell cycle regulators and oncoproteins, contributing to tumorigenesis. | COSMIC; literature review |
| Intellectual disability (candidate) | Chromosomal rearrangements involving 12q24.21 have been reported in patients with developmental delay, though direct evidence for FBXO21 is limited. | OMIM; ClinVar |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 12.5 | Medium |
| Lymph node | 10.2 | Medium |
| Spleen | 9.8 | Medium |
| Bone marrow | 8.5 | Medium |
| Brain | 6.3 | Low |
| Liver | 4.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK 293 | 15.0 | Embryonic kidney; high expression |
| HeLa | 12.3 | Cervical carcinoma; moderate expression |
| K562 | 10.5 | Leukemia; moderate expression |
| A549 | 8.2 | Lung carcinoma; low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1045C>T (p.Arg349Trp) | Missense | <0.01% | Unknown; reported in COSMIC |
| c.1234G>A (p.Glu412Lys) | Missense | <0.01% | Unknown; reported in COSMIC |
| c.789_790insA | Frameshift | <0.01% | Predicted loss of function |
Mutation functional classification
Loss of Function (LOF)
Frameshift or nonsense mutations that truncate the F-box domain or substrate-binding region are predicted to impair SCF complex assembly and ubiquitination activity.
Gain of Function (GOF)
No confirmed gain-of-function mutations have been reported for FBXO21.
Dominant Negative (DN)
Missense mutations in the F-box domain may produce a dominant-negative effect by competing with wild-type FBXO21 for SCF complex binding.
View complete mutation data：
Gene Ontology (GO)
| • protein binding (GO:0005515) | • ubiquitin-dependent protein catabolic process (GO:0006511) |
| • protein ubiquitination (GO:0016567) | • SCF-dependent proteasomal ubiquitin-dependent protein catabolic process (GO:0031146) |
| • proteasome-mediated ubiquitin-dependent protein catabolic process (GO:0043161) |
Pathways
• SCF ubiquitin ligase complex pathway
• Ubiquitin-proteasome pathway
• Cell cycle regulation
Protein Summary
FBXO21 is a 522-amino acid protein containing an N-terminal F-box domain (residues 32-79) and a C-terminal substrate-binding region. It functions as the substrate recognition component of the SCF ubiquitin ligase complex, targeting phosphorylated proteins for ubiquitination and degradation. The protein is localized to the nucleus and cytoplasm and is involved in regulating cell cycle progression and signal transduction.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| FBXO21 Knockout HEK293 Cell Line | EDJ-KQ2318 | Human | 23014 | Details Get a Quote |
| FBXO21 Knockout A-549 Cell Line | EDJ-KQ24077 | Human | 23014 | Details Get a Quote |
| FBXO21 Knockout HCT 116 Cell Line | EDJ-KQ24078 | Human | 23014 | Details Get a Quote |
| FBXO21 Knockout HeLa Cell Line | EDJ-KQ24079 | Human | 23014 | Details Get a Quote |
