UPF3B
UPF3B, regulator of nonsense mediated mRNA decay
Gene Information Card
| Symbol | UPF3B |
|---|---|
| Full Name | UPF3B, regulator of nonsense mediated mRNA decay |
| Gene Type | Protein coding |
| Chromosomal Location | Xq24 |
| NCBI Gene ID | 65109 ncbi.nlm.nih.gov/gene/65109 |
| Ensembl ID | ENSG00000100156 |
| UniProt ID | Q9BZI7 |
| OMIM ID | 300298 |
| HGNC ID | 20439 |
| Aliases | UPF3X, RENT3B, MRXS14 |
Description
UPF3B (UPF3B, regulator of nonsense mediated mRNA decay) is a protein-coding gene located on the X chromosome. It encodes a component of the exon junction complex (EJC) that is essential for nonsense-mediated mRNA decay (NMD), a surveillance pathway that degrades mRNAs containing premature termination codons. Mutations in UPF3B are associated with X-linked intellectual disability and other neurodevelopmental disorders.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| X-linked intellectual disability 14 (MRXS14) | Loss-of-function mutations impair NMD, leading to accumulation of aberrant transcripts and disrupted neuronal gene expression | ClinVar, OMIM |
| Syndromic X-linked intellectual disability | Disruption of NMD pathway affects synaptic plasticity and neurodevelopment | OMIM |
| Autism spectrum disorder | UPF3B variants may contribute to ASD risk through NMD dysregulation | ClinVar |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 15.2 | Medium |
| Testis | 12.8 | Medium |
| Heart | 8.5 | Low |
| Liver | 6.3 | Low |
| Kidney | 7.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 18.5 | High expression |
| HeLa | 14.2 | Medium expression |
| SH-SY5Y | 16.0 | High expression |
| K562 | 9.8 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1000C>T (p.Arg334*) | Nonsense | Rare | Loss of function, NMD impairment |
| c.679C>T (p.Arg227*) | Nonsense | Rare | Loss of function, NMD impairment |
| c.2T>C (p.Met1?) | Missense | Rare | Loss of function, NMD impairment |
Mutation functional classification
Loss of Function (LOF)
Most UPF3B mutations are loss-of-function, leading to reduced NMD activity and accumulation of aberrant transcripts.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported.
View complete mutation data：
Gene Ontology (GO)
| • nonsense-mediated mRNA decay | • RNA binding |
| • exon junction complex | • nuclear speck |
| • cytoplasm |
Pathways
• Nonsense-mediated mRNA decay (NMD)
• mRNA surveillance pathway
Protein Summary
UPF3B is a 483-amino acid protein that localizes to the nucleus and cytoplasm. It is a core component of the exon junction complex (EJC) and interacts with UPF2 and UPF1 to trigger NMD. The protein contains a UPF3 domain and is essential for recognizing premature termination codons and initiating mRNA decay.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| UPF3B Knockout HEK293 Cell Line | EDJ-KQ16036 | Human | 65109 | Details Get a Quote |
| UPF3B Knockout A-549 Cell Line | EDJ-KQ47140 | Human | 65109 | Details Get a Quote |
| UPF3B Knockout HCT 116 Cell Line | EDJ-KQ47141 | Human | 65109 | Details Get a Quote |
| UPF3B Knockout HeLa Cell Line | EDJ-KQ47142 | Human | 65109 | Details Get a Quote |
