Recombinant Human Extracellular glycoprotein lacritin (LACRT)

1. Data show increased levels of lysozyme C (LYZ), lacritin (LACRT) and zinc-alpha-2 glycoprotein 1 (AZGP1) in pooled tear fluid sample from Graves' disease (GD) patients with moderate-to-severe Graves' orbitopathy (GO) compared with GD patients without clinical signs of GO. PMID: 28419103
2. cytoprotective effect of lacritin is mediated through Cyclooxygenase-2 (COX-2). PMID: 26670139
3. the C terminus of lacritin is multifunctional by dose and proteolytic processing and appears to play a key role in the innate protection of the eye PMID: 24942736
4. Lacritin is a component of vampire bat saliva, as detected by mass spectrometry. PMID: 23748026
5. Study involving 129 dry eye disease patients and 73 healthy controls, revealing significantly less tear lacritin in 95% of patients. Lacritin was one of seven proteins downregulated PMID: 23272196
6. iTRAQ analysis suggests that lacritin is selectively deficient in tears of patients with aqueous deficient dry eye. PMID: 22736608
7. Horse lacritin is 45% identical to human, and shares a predicted amphipathic alpha helix important for cell targeting. PMID: 22871838
8. A direct ELISA was established to estimate lacritin levels in tears. An ELISA estimate of 4.2 ng lacritin per 100 ng total tear protein did not vary significantly among individuals of different ages (18 - 52 years), or gender. PMID: 22918641
9. Lacritin mRNA is the 24st most abundant in the lacrimal gland of Wolfring. Lacritin protein is detected by immunofluorescence. PMID: 22956620
10. Lacritin is 10-fold less in tears from individuals suffering from fungal keratitis, and is barely detectable in the initial stage of infection by Fusarium solani. Fungal keratitis accounts for half of all corneal ulcers in Africa and India. PMID: 23308132
11. Genomic analysis expands the number of predicted lacritin orthologs, and suggests that secondary structure may be largely conserved. All currently known tear proteins predicted to be extracellular by GEO are assembled, and functions summarized. PMID: 23769845
12. Tissue transglutaminase promotes crosslinking of lacritin between K82 or K85 and Q106 - the latter residing in the SDC1 binding domain of lacritin necessary for cell targeting, thus inactivating lacritin. Tissue transglutaminase is thought to be upregulated in dry eye, the most common eye disease. PMID: 23425695
13. Lacritin rapidly and transiently accelerates autophagy to rid stressed cells of aggregated proteins. Lacritin also restores oxidative phosphorylation. LC3-II, in the absence of autophagic inhibitor, decreases as a consequence of rapidly increased flux. PMID: 23640897
14. Lacritin stimulates tear protein secretion from lacrimal acinar cells stressed with inflammatory cytokines, however under the same conditions carbachol is completely ineffective. Inflammatory cytokines are elevated in dry eye, the most common eye disease. The implication is that topical lacritin might be an effective therapeutic for dry eye. PMID: 23482462
15. Targeting of heparanase-modified syndecan-1 by prosecretory mitogen lacritin requires conserved core GAGAL plus heparan and chondroitin sulfate as a novel hybrid binding site that enhances selectivity. PMID: 23504321
16. Lacritin protein yields were improved primarily by hydrophobic or salt bridge mutagenesis and less so by elimination of rare codons. PMID: 23422824
17. Monkey lacrimal acinar cells release lacritin upon carbachol stimulation. Pro-secretory signaling involves PKC and calcium, but not MAPK. PMID: 20375347
18. Lacritin was detected in monkey tear fluid. Among monkey ocular tissues, lacritin mRNA is highly expressed highly in lacrimal gland, somewhat less so in conjunctiva and meibomian gland, and slightly in corneal epithelium. PMID: 17850790
19. Lacritin from tears is deposited on all contact lenses tested, and one of 19 tear proteins identified. PMID: 18334948
20. In tears of patients with climatic droplet keratopathy, N-linked glycosylation of lacritin is decreased, although the quantity of lacritin is unaltered. PMID: 19714880
21. Lacritin was found to be decreased in tears of patients with contact lens related dry eye. PMID: 19770725
22. Lacritin gene maps near but not within triple A syndome region. Alacrimia in triple a syndrome not due to mutation in lacritin gene. PMID: 12613904
23. expressed in human breast tumors, breast cancer cell lines, and normal breast PMID: 14574570
24. Lacritin is one of nine tear proteins downregulated in patients suffering from blepharitis, or inflammation of the eyelid often associated with dry eye. PMID: 15952718
25. Lacritin is detected by MS in meibomian gland secretions. PMID: 16488965
26. Lacritin is detected in human tears by mass spectometry from patients with pterygium. PMID: 16865190
27. Heparanase cleavage of SDC1 heparan sulfate chains is required for lacritin binding. This mechanism therefore forms a novel off/on switch for lacritin-dependent mitogenesis. PMID: 16982797
28. Lacritin binds a form of SDC1 that lacks or contains short heparan sulfate chains, as revealed by gel filtration of chemically cleaved chains. Also by binding studies with FGF2 purified SDC1 with or without heparitinase digestion. PMID: 16982797
29. Lacritin binds human SDC1, but not human SDC2 or SDC4. Lacritin C-5, C-10, N-15, N-24, but not C-25 binds SDC1. C-15 weakly binds. Thus the C-terminal mitogenic and SDC1 binding domains appear to be the same. PMID: 16982797
30. Lacritin mitogenesis and COX2 expression is abrogated when SDC1 (but not SDC2) is depleted by siRNA. Similarly siRNA depletion of HPSE1 (but not HPSE2) knocks out lacritin mitogenesis and can be rescued by exogenous HPSE1. PMID: 16982797
31. Lacritin calcium signaling is inhibited by pertussis toxin, U73122 and Go 6976. PMID: 16923831
32. Lacritin displays restricted cell target specificity in a screen of 17 different cell types. It targets rat lacrimal acinar, human corneal epithelial (HCE-T), human salivary ductal (HSG) and human embryonal kidney cells (HEK293). PMID: 16923831
33. Lacritin signaling drives the formation of a Golgi PKCalpha/PLD1/PLCgamma2 complex. PMID: 16923831
34. Lacritin-dependent mitogenesis is abrogated by siRNA depletion of NFATC1, mTOR and STIM1, but not TRPC1. Also cyclosporin and rapamycin inhibit. This same pattern is observed in affect on lacritin-stimulated COX2 mRNA expression. PMID: 16923831
35. Lacritin's C-terminus is required for mitogenesis. C-10 is fully active, C-15 has approximately half the activity and C-20 is inactive. PMID: 16923831
36. Lacritin's signaling and mitogenic responses are biphasic (1- 10 nM dose optimum). Its biphasic signaling includes rapid PKCalpha dephosphorylation, and PLD1, calcineurin and NFATC1 activation. PMID: 16923831
37. Lacritin binds several basment membrane components (collagen IV, nidogen, fibronectin, laminin-1). Also vitronectin, but not collagen I or heparin. Yet it is secreted apically and possibly may form non-covalent complexes with tear fibronectin. PMID: 11419941
38. Lacritin is detected in human tears and promotes tear secretion in vitro when added to rat lacrimal acinar cells via a pathway apparently independent of the M3 receptor. It is mitogenic at low ng/ml levels for salivary ductal cells. PMID: 11419941
39. Tissue microarray of seventy-five different human tissues, including mammary gland, detected expression only in lacrimal acinar and salivary ductal cells. Thyroid immunostaining was equivocal. These data agree with Clonetech RNA dot blot analysis. PMID: 11419941
40. Lacritin is the sixth most common transcript in the human lacrimal gland based on EST sequencing, and is one of twenty-nine 'lacrimal preferred' genes. PMID: 15851553

Show More

Hide All

HGNC: 16430

OMIM: 607360

KEGG: hsa:90070

STRING: 9606.ENSP00000257867

UniGene: Hs.307096