UBL4A: Ubiquitin-Like 4A, a Key Component of the BAG6 Complex
Comprehensive genomic, functional, and clinical overview of UBL4A (GDX), a ubiquitin-like protein involved in protein quality control and DNA repair.
Gene Information Card
| Symbol | UBL4A |
|---|---|
| Full Name | Ubiquitin-Like 4A |
| Gene Type | Protein coding |
| Chromosomal Location | Xq28 |
| NCBI Gene ID | 8266 ncbi.nlm.nih.gov/gene/8266 |
| Ensembl ID | ENSG00000102144 |
| UniProt ID | P11441 |
| OMIM ID | 312070 |
| HGNC ID | 12513 |
| Aliases | GDX, UBL4, NICE-4, PNAS-22 |
Description
UBL4A (Ubiquitin-Like 4A) encodes a ubiquitin-like protein that is a core component of the BAG6 complex, which mediates the post-translational delivery of tail-anchored membrane proteins to the endoplasmic reticulum and targets mislocalized proteins for proteasomal degradation. The protein also participates in DNA damage repair and apoptosis regulation. UBL4A is located on the X chromosome and is widely expressed across tissues.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Cancer (multiple types) | Somatic mutations and altered expression may disrupt protein quality control and DNA repair, promoting genomic instability. | COSMIC, ClinVar |
| Neurodegenerative disorders | Impaired BAG6 complex function may lead to accumulation of mislocalized proteins, contributing to neuronal toxicity. | UniProt, literature |
| X-linked intellectual disability | Potential involvement due to Xq28 location and role in protein homeostasis, though direct evidence is limited. | OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 28.5 | High |
| Lymph node | 22.1 | High |
| Spleen | 20.3 | High |
| Brain | 15.2 | Medium |
| Liver | 12.8 | Medium |
| Heart | 10.5 | Medium |
| Lung | 8.9 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK 293 | 25.0 | High expression |
| HeLa | 22.3 | High expression |
| K562 | 18.7 | Medium expression |
| A549 | 15.1 | Medium expression |
| MCF7 | 12.4 | Medium expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Missense | <0.01% | Likely loss of start codon; predicted loss of function |
| c.214C>T (p.Arg72Cys) | Missense | 0.02% | May affect protein stability; reported in cancer samples |
| c.328G>A (p.Gly110Ser) | Missense | 0.01% | Observed in COSMIC; functional impact unknown |
Mutation functional classification
Loss of Function (LOF)
Mutations that disrupt the start codon or introduce premature stop codons are predicted to cause loss of UBL4A function, impairing BAG6 complex activity and protein quality control.
Gain of Function (GOF)
No gain-of-function mutations have been reported for UBL4A.
Dominant Negative (DN)
No dominant-negative mutations have been characterized for UBL4A.
View complete mutation data：
Gene Ontology (GO)
Pathways
• BAG6 complex-mediated protein quality control (Reactome: R-HSA-983168)
• Tail-anchored protein insertion into ER membrane (Reactome: R-HSA-983189)
• p53-independent DNA damage response
Protein Summary
UBL4A is a 157-amino-acid ubiquitin-like protein (UniProt P11441) that lacks the canonical C-terminal diglycine motif required for ubiquitin conjugation. It functions as an adaptor within the BAG6 complex, bridging the recognition of mislocalized proteins and their delivery to the proteasome. The protein is localized to the cytoplasm and nucleus, and its expression is ubiquitous with enrichment in testis and lymphoid tissues.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| UBL4A Knockout HEK293 Cell Line | EDJ-KQ50747 | Human | 8266 | Details Get a Quote |
| UBL4A Knockout HeLa Cell Line | EDJ-KQ54841 | Human | 8266 | Details Get a Quote |
| UBL4A Knockout A-549 Cell Line | EDJ-KQ63332 | Human | 8266 | Details Get a Quote |
| UBL4A Knockout HCT 116 Cell Line | EDJ-KQ71802 | Human | 8266 | Details Get a Quote |
