| 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]
Publication Abstract from PubMed
Langerin, a trimeric C-type lectin specifically expressed in Langerhans cells, has been reported to be a pathogen receptor through the recognition of glycan motifs by its three carbohydrate recognition domains (CRD). In the context of HIV-1 (human immunodeficiency virus-1) transmission, Langerhans cells of genital mucosa play a protective role by internalizing virions in Birbeck Granules (BG) for elimination. Langerin (Lg) is directly involved in virion binding and BG formation through its CRDs. However, nothing is known regarding the mechanism of langerin assembly underlying BG formation. We investigated at the molecular level the impact of two CRD mutations, W264R and F241L, on langerin structure, function, and BG assembly using a combination of biochemical and biophysical approaches. Although the W264R mutation causes CRD global unfolding, the F241L mutation does not affect the overall structure and gp120 (surface HIV-1 glycoprotein of 120 kDa) binding capacities of isolated Lg-CRD. In contrast, this mutation induces major functional and structural alterations of the whole trimeric langerin extracellular domain (Lg-ECD). As demonstrated by small-angle x-ray scattering comparative analysis of wild-type and mutant forms, the F241L mutation perturbs the oligomerization state and the global architecture of Lg-ECD. Correlatively, despite conserved intrinsic lectin activity of the CRD, avidity property of Lg-ECD is affected as shown by a marked decrease of gp120 binding. Beyond the change of residue itself, the F241L mutation induces relocation of the K200 side chain also located within the interface between protomers of trimeric Lg-ECD, thereby explaining the defective oligomerization of mutant Lg. We conclude that not only functional CRDs but also their correct spatial presentation are critical for BG formation as well as gp120 binding.
Alteration of the langerin oligomerization state affects birbeck granule formation.,Chabrol E, Thepaut M, Dezutter-Dambuyant C, Vives C, Marcoux J, Kahn R, Valladeau-Guilemond J, Vachette P, Durand D, Fieschi F Biophys J. 2015 Feb 3;108(3):666-77. doi: 10.1016/j.bpj.2014.10.075. PMID:25650933[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ Chabrol E, Thepaut M, Dezutter-Dambuyant C, Vives C, Marcoux J, Kahn R, Valladeau-Guilemond J, Vachette P, Durand D, Fieschi F. Alteration of the langerin oligomerization state affects birbeck granule formation. Biophys J. 2015 Feb 3;108(3):666-77. doi: 10.1016/j.bpj.2014.10.075. PMID:25650933 doi:http://dx.doi.org/10.1016/j.bpj.2014.10.075
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