KPNA4: Karyopherin Subunit Alpha 4
Nuclear import receptor involved in nucleocytoplasmic transport and cellular signaling
Gene Information Card
| Symbol | KPNA4 |
|---|---|
| Full Name | Karyopherin Subunit Alpha 4 |
| Gene Type | Protein coding |
| Chromosomal Location | 3q25.33 |
| NCBI Gene ID | 3840 ncbi.nlm.nih.gov/gene/3840 |
| Ensembl ID | ENSG00000114771 |
| UniProt ID | O00629 |
| OMIM ID | 602652 |
| HGNC ID | 6398 |
| Aliases | IPOA4, QIP1, SRP3, hSRP1gamma, RCH2 |
Description
KPNA4 encodes karyopherin subunit alpha 4, a member of the importin alpha family that mediates nuclear import of proteins containing a classical nuclear localization signal (NLS). The protein functions as an adapter between cargo proteins and the importin beta subunit, facilitating translocation through the nuclear pore complex. KPNA4 is involved in diverse cellular processes including cell cycle regulation, signal transduction, and viral infection.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Cancer (various types) | Altered KPNA4 expression may affect nuclear transport of tumor suppressors and oncogenes | COSMIC, literature |
| Viral infections (e.g., HIV, influenza) | KPNA4 mediates nuclear import of viral proteins | UniProt, literature |
| Primary biliary cholangitis | Potential role in immune dysregulation via nuclear transport of transcription factors | OMIM, literature |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 18.5 | High |
| Lymph node | 14.2 | High |
| Spleen | 13.8 | High |
| Bone marrow | 12.1 | High |
| Lung | 9.5 | Medium |
| Brain | 6.3 | Medium |
| Liver | 4.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK 293 | 15.2 | Embryonic kidney, high expression |
| HeLa | 12.8 | Cervical carcinoma, high expression |
| K562 | 11.5 | Leukemia, high expression |
| A549 | 9.7 | Lung carcinoma, medium expression |
| HepG2 | 6.3 | Hepatocellular carcinoma, medium expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1012C>T (p.Arg338Trp) | Missense | <0.01% | Unknown; rare variant in population databases |
| c.1456G>A (p.Glu486Lys) | Missense | <0.01% | Unknown; rare variant in population databases |
| c.1687C>T (p.Arg563Cys) | Missense | <0.01% | Unknown; rare variant in population databases |
Mutation functional classification
Loss of Function (LOF)
No confirmed loss-of-function mutations reported in ClinVar or COSMIC.
Gain of Function (GOF)
No confirmed gain-of-function mutations reported.
Dominant Negative (DN)
No confirmed dominant-negative mutations reported.
View complete mutation data：
Gene Ontology (GO)
| • protein import into nucleus (GO:0006606) | • nuclear localization sequence binding (GO:0008139) |
| • protein transporter activity (GO:0008565) | • viral process (GO:0016032) |
| • regulation of protein export from nucleus (GO:0046822) | • mRNA transport (GO:0051028) |
Pathways
• REACT:168256 - Immune System
• REACT:170834 - Transport of Mature mRNA derived from an Intron-Containing Transcript
• REACT:212300 - HIV Life Cycle
• REACT:213045 - Nuclear import of viral proteins
Protein Summary
KPNA4 (importin alpha 4) is a 58 kDa protein that belongs to the importin alpha family. It contains an N-terminal importin beta binding domain (IBB) and 10 armadillo (ARM) repeats that form a groove for NLS recognition. KPNA4 shuttles between nucleus and cytoplasm, binding cargo proteins in the cytoplasm and releasing them in the nucleus after interaction with RanGTP. It is ubiquitously expressed with highest levels in testis and lymphoid tissues. KPNA4 has been implicated in cancer progression and viral pathogenesis.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| KPNA4 Knockout HEK293 Cell Line | EDJ-KQ5081 | Human | 3840 | Details Get a Quote |
| KPNA4 Knockout A-549 Cell Line | EDJ-KQ28011 | Human | 3840 | Details Get a Quote |
| KPNA4 Knockout HCT 116 Cell Line | EDJ-KQ28012 | Human | 3840 | Details Get a Quote |
| KPNA4 Knockout HeLa Cell Line | EDJ-KQ28013 | Human | 3840 | Details Get a Quote |
