LACRT (Lacritin)
A secreted glycoprotein involved in tear film stability and corneal epithelial cell proliferation
Gene Information Card
| Symbol | LACRT |
|---|---|
| Full Name | Lacritin |
| Gene Type | Protein coding |
| Chromosomal Location | 12q13.2 |
| NCBI Gene ID | 90070 ncbi.nlm.nih.gov/gene/90070 |
| Ensembl ID | ENSG00000135423 |
| UniProt ID | Q9GZZ8 |
| OMIM ID | 607360 |
| HGNC ID | 23059 |
| Aliases | LACRT1, LACRT2, LACRT3 |
Description
LACRT encodes lacritin, a secreted glycoprotein predominantly expressed in lacrimal gland and corneal epithelium. Lacritin promotes tear secretion, maintains tear film stability, and stimulates corneal epithelial cell proliferation. It is implicated in dry eye disease and ocular surface inflammation.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Dry Eye Disease | Reduced lacritin levels impair tear film stability and corneal epithelial homeostasis | ClinVar, NCBI |
| Keratoconjunctivitis Sicca | Decreased lacritin expression correlates with ocular surface inflammation | NCBI, OMIM |
| Sjögren's Syndrome | Autoimmune-mediated reduction of lacritin secretion contributes to dry eye symptoms | NCBI |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Lacrimal Gland | 112.3 | High |
| Corneal Epithelium | 45.6 | Medium |
| Salivary Gland | 38.2 | Medium |
| Trachea | 12.1 | Low |
| Lung | 8.5 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HCE (human corneal epithelial) | 78.4 | High expression |
| ARPE-19 (retinal pigment epithelium) | 22.1 | Moderate expression |
| HeLa | 5.3 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.152C>T (p.Pro51Leu) | Missense | 0.02% | Reduced secretion and stability |
| c.218G>A (p.Arg73His) | Missense | 0.01% | Altered glycosylation |
| c.1A>G (p.Met1Val) | Start loss | <0.01% | Loss of protein expression |
Mutation functional classification
Loss of Function (LOF)
Missense variants (e.g., p.Pro51Leu) impair lacritin secretion and reduce corneal epithelial proliferation.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations described.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Extracellular matrix organization (Reactome: R-HSA-1474244)
• Signaling by receptor tyrosine kinases (Reactome: R-HSA-9006934)
Protein Summary
Lacritin is a 12.3 kDa secreted glycoprotein composed of 119 amino acids. It contains a signal peptide (residues 1–19) and a mature peptide (residues 20–119). Lacritin binds to cell surface receptors, activating MAPK/ERK signaling to promote corneal epithelial cell proliferation and migration. It also interacts with fibronectin and laminin to support tear film stability. Post-translational modifications include N-glycosylation at Asn-95.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| LACRT Knockout HEK293 Cell Line | EDJ-KQ10552 | Human | 90070 | Details Get a Quote |
| LACRT Knockout HeLa Cell Line | EDJ-KQ57757 | Human | 90070 | Details Get a Quote |
| LACRT Knockout A-549 Cell Line | EDJ-KQ66251 | Human | 90070 | Details Get a Quote |
| LACRT Knockout HCT 116 Cell Line | EDJ-KQ74673 | Human | 90070 | Details Get a Quote |
