LNPK (Lunapark, ER Junction Formation Factor)
Gene encoding a protein involved in endoplasmic reticulum junction formation and calcium homeostasis.
Gene Information Card
| Symbol | LNPK |
|---|---|
| Full Name | Lunapark, ER Junction Formation Factor |
| Gene Type | Protein coding |
| Chromosomal Location | 2q31.2 |
| NCBI Gene ID | 80856 ncbi.nlm.nih.gov/gene/80856 |
| Ensembl ID | ENSG00000144381 |
| UniProt ID | Q9C0E8 |
| OMIM ID | 610236 |
| HGNC ID | 21676 |
| Aliases | FLJ12505, KIAA1715, LNP |
Description
LNPK encodes the lunapark protein, a component of the endoplasmic reticulum (ER) membrane that localizes to three-way ER junctions. It is involved in maintaining ER morphology, calcium homeostasis, and neuronal development. Mutations in LNPK are associated with autosomal recessive neurodevelopmental disorders.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Neurodevelopmental disorder with microcephaly, spasticity, and brain abnormalities | Loss of function leads to disrupted ER junction formation and calcium dysregulation | PMID: 28965846, ClinVar |
| Autosomal recessive intellectual disability | Impaired ER morphology and synaptic function | PMID: 28965846 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 15.2 | Medium |
| Testis | 8.5 | Low |
| Kidney | 6.1 | Low |
| Liver | 4.3 | Low |
| Heart | 3.9 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| SH-SY5Y (neuroblastoma) | 12.1 | Neuronal model |
| HEK293 (embryonic kidney) | 8.7 | Common expression system |
| HeLa (cervical carcinoma) | 6.4 | Epithelial model |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Missense | Rare | Loss of start codon, likely loss of function |
| c.325C>T (p.Arg109*) | Nonsense | Rare | Premature stop, loss of function |
| c.494G>A (p.Arg165His) | Missense | Rare | Impaired ER junction localization |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations lead to truncated protein and loss of ER junction formation.
Gain of Function (GOF)
Not reported.
Dominant Negative (DN)
Not reported.
View complete mutation data：
Gene Ontology (GO)
| • endoplasmic reticulum (GO:0005783) | • dendritic spine (GO:0043197) |
| • calcium ion homeostasis (GO:0051209) | • integral component of membrane (GO:0016021) |
| • neuronal cell body (GO:0043025) |
Pathways
• Endoplasmic reticulum membrane organization
• Calcium signaling pathway
Protein Summary
Lunapark is a 445-amino acid transmembrane protein with a conserved zinc finger domain. It localizes to ER three-way junctions and stabilizes the ER network. It interacts with reticulons and REEP proteins to shape ER tubules. In neurons, it is essential for dendritic spine formation and calcium signaling.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| LNPK Knockout HEK293 Cell Line | EDJ-KQ9591 | Human | 80856 | Details Get a Quote |
| LNPK Knockout A-549 Cell Line | EDJ-KQ36422 | Human | 80856 | Details Get a Quote |
| LNPK Knockout HCT 116 Cell Line | EDJ-KQ36423 | Human | 80856 | Details Get a Quote |
| LNPK Knockout HeLa Cell Line | EDJ-KQ36424 | Human | 80856 | Details Get a Quote |
