LEKTI-2
Lympho-epithelial Kazal-type related inhibitor 2 (LEKTI-2) is a protein encoded by the SPINK9 gene in humans. SPINK9 is a member of a gene family cluster located on chromosome 5q33.1, which includes SPINK5 and SPINK6.[3] LEKTI-2 is an inhibitor of KLK5.
| SPINK9 | |||||||||||||||||||||||||||||||||||||||||||||||||||
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| Aliases | SPINK9, LEKTI2, serine peptidase inhibitor, Kazal type 9, serine peptidase inhibitor Kazal type 9 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| External IDs | OMIM: 613511 HomoloGene: 88638 GeneCards: SPINK9 | ||||||||||||||||||||||||||||||||||||||||||||||||||
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Desquamation
The outer layer of the epidermis is called the stratum corneum. In the stratum corneum terminally differentiated corneocytes are held together by corneodesmosomes. In order for desquamation to occur, corneodesmosomes need to be fully degraded. KLK5 and KLK7 are two serine proteases that degrade corneodesmosomes. LEKTI-2 regulates corneodesmosome degradation by inhibiting KLK5. In acral (palm and sole) skin, where desquamation needs to be delayed, SPINK9 expression is strongly upregulated.[4] The resulting high level of LEKTI-2 delays corneodesmosome degradation, thereby allowing the epidermis to form a thick protective stratum corneum layer.[4]
Clinical Significance
SPINK9 is overexpressed in lichen simplex chronicus, actinic keratosis, and squamous cell carcinoma.[5]
References
- GRCh38: Ensembl release 89: ENSG00000204909 - Ensembl, May 2017
- "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- Furio L, Hovnanian A (November 2011). "When activity requires breaking up: LEKTI proteolytic activation cascade for specific proteinase inhibition". The Journal of Investigative Dermatology. 131 (11): 2169–2173. doi:10.1038/jid.2011.295. PMID 21997416.
- Merleev AA, Le ST, Alexanian C, Toussi A, Xie Y, Marusina AI, et al. (August 2022). "Biogeographic and disease-specific alterations in epidermal lipid composition and single-cell analysis of acral keratinocytes". JCI Insight. 7 (16): e159762. doi:10.1172/jci.insight.159762. PMC 9462509. PMID 35900871.
- Redelfs L, Fischer J, Weber C, Wu Z, Meyer-Hoffert U (March 2016). "The serine protease inhibitor of Kazal-type 9 (SPINK9) is expressed in lichen simplex chronicus, actinic keratosis and squamous cell carcinoma". Archives of Dermatological Research. 308 (2): 133–137. doi:10.1007/s00403-015-1616-5. PMID 26746658. S2CID 42382142.