7ytq

Structural highlights

Disease

CLC4K_HUMAN Defects in CD207 are the cause of Birbeck granule deficiency (BIRGD) [MIM:613393. It is a condition characterized by the absence of Birbeck granules in epidermal Langerhans cells. Despite the lack of Birbeck granules Langerhans cells are present in normal numbers and have normal morphologic characteristics and antigen-presenting capacity.^{[1] [2]}

Function

CLC4K_HUMAN Calcium-dependent lectin displaying mannose-binding specificity. Induces the formation of Birbeck granules (BGs); is a potent regulator of membrane superimposition and zippering. Binds to sulfated as well as mannosylated glycans, keratan sulfate (KS) and beta-glucans. Facilitates uptake of antigens and is involved in the routing and/or processing of antigen for presentation to T cells. Major receptor on primary Langerhans cells for Candida species, Saccharomyces species, and Malassezia furfur. Protects against human immunodeficiency virus-1 (HIV-1) infection. Binds to high-mannose structures present on the envelope glycoprotein which is followed by subsequent targeting of the virus to the Birbeck granules leading to its rapid degradation.^{[3] [4] [5] [6]}

References

1. ↑ Verdijk P, Dijkman R, Plasmeijer EI, Mulder AA, Zoutman WH, Mieke Mommaas A, Tensen CP. A lack of Birbeck granules in Langerhans cells is associated with a naturally occurring point mutation in the human Langerin gene. J Invest Dermatol. 2005 Apr;124(4):714-7. PMID:15816828 doi:10.1111/j.0022-202X.2005.23645.x
2. ↑ Ward EM, Stambach NS, Drickamer K, Taylor ME. Polymorphisms in human langerin affect stability and sugar binding activity. J Biol Chem. 2006 Jun 2;281(22):15450-6. Epub 2006 Mar 27. PMID:16567809 doi:10.1074/jbc.M511502200
3. ↑ Valladeau J, Ravel O, Dezutter-Dambuyant C, Moore K, Kleijmeer M, Liu Y, Duvert-Frances V, Vincent C, Schmitt D, Davoust J, Caux C, Lebecque S, Saeland S. Langerin, a novel C-type lectin specific to Langerhans cells, is an endocytic receptor that induces the formation of Birbeck granules. Immunity. 2000 Jan;12(1):71-81. PMID:10661407
4. ↑ de Witte L, Nabatov A, Pion M, Fluitsma D, de Jong MA, de Gruijl T, Piguet V, van Kooyk Y, Geijtenbeek TB. Langerin is a natural barrier to HIV-1 transmission by Langerhans cells. Nat Med. 2007 Mar;13(3):367-71. Epub 2007 Mar 4. PMID:17334373 doi:10.1038/nm1541
5. ↑ Tateno H, Ohnishi K, Yabe R, Hayatsu N, Sato T, Takeya M, Narimatsu H, Hirabayashi J. Dual specificity of Langerin to sulfated and mannosylated glycans via a single C-type carbohydrate recognition domain. J Biol Chem. 2010 Feb 26;285(9):6390-400. doi: 10.1074/jbc.M109.041863. Epub 2009, Dec 21. PMID:20026605 doi:10.1074/jbc.M109.041863
6. ↑ de Jong MA, Vriend LE, Theelen B, Taylor ME, Fluitsma D, Boekhout T, Geijtenbeek TB. C-type lectin Langerin is a beta-glucan receptor on human Langerhans cells that recognizes opportunistic and pathogenic fungi. Mol Immunol. 2010 Mar;47(6):1216-25. doi: 10.1016/j.molimm.2009.12.016. Epub 2010, Jan 25. PMID:20097424 doi:10.1016/j.molimm.2009.12.016