1. Academic Validation
  2. AP1S3 mutations are associated with pustular psoriasis and impaired Toll-like receptor 3 trafficking

AP1S3 mutations are associated with pustular psoriasis and impaired Toll-like receptor 3 trafficking

  • Am J Hum Genet. 2014 May 1;94(5):790-7. doi: 10.1016/j.ajhg.2014.04.005.
Niovi Setta-Kaffetzi 1 Michael A Simpson 1 Alexander A Navarini 1 Varsha M Patel 1 Hui-Chun Lu 2 Michael H Allen 1 Michael Duckworth 1 Hervé Bachelez 3 A David Burden 4 Siew-Eng Choon 5 Christopher E M Griffiths 6 Brian Kirby 7 Antonios Kolios 8 Marieke M B Seyger 9 Christa Prins 10 Asma Smahi 11 Richard C Trembath 12 Franca Fraternali 2 Catherine H Smith 1 Jonathan N Barker 1 Francesca Capon 13
Affiliations

Affiliations

  • 1 Division of Genetics and Molecular Medicine, King's College London, London SE1 9RT, UK.
  • 2 Randall Division of Cell and Molecular Biophysics, King's College London, London SE1 9RT, UK.
  • 3 Institut National de la Santé et de la Recherche Médicale Unité 781, Institut Imagine, Hopital Necker - Enfant Malades, Paris 75015, France; Department of Dermatology, Sorbonne Paris Cité Université Paris Diderot and Hôpital Saint-Louis, Assistance Publique - Hôpitaux de Paris, Paris 75010, France.
  • 4 Department of Dermatology, University of Glasgow, Glasgow G11 6NT, UK.
  • 5 Department of Dermatology, Hospital Sultanah Aminah, Johor Bahru 80100, Malaysia.
  • 6 Department of Dermatology, University of Manchester, Manchester M6 8HD, UK.
  • 7 Department of Dermatology, St. Vincent University Hospital, Dublin 4, Ireland.
  • 8 Department of Dermatology, Zurich University Hospital, Zurich 8091, Switzerland.
  • 9 Department of Dermatology, Radboud University Nijmegen Medical Centre, 6500HB Nijmegen, the Netherlands.
  • 10 Dermatology Service, Geneva University Hospital, 1211 Geneva 14, Switzerland.
  • 11 Institut National de la Santé et de la Recherche Médicale Unité 781, Institut Imagine, Hopital Necker - Enfant Malades, Paris 75015, France.
  • 12 Division of Genetics and Molecular Medicine, King's College London, London SE1 9RT, UK; Queen Mary University of London, Barts and The London School of Medicine and Dentistry, London EC1M 6QB, UK.
  • 13 Division of Genetics and Molecular Medicine, King's College London, London SE1 9RT, UK. Electronic address: [email protected].
Abstract

Adaptor protein complex 1 (AP-1) is an evolutionary conserved heterotetramer that promotes vesicular trafficking between the trans-Golgi network and the endosomes. The knockout of most murine AP-1 complex subunits is embryonically lethal, so the identification of human disease-associated alleles has the unique potential to deliver insights into gene function. Here, we report two founder mutations (c.11T>G [p.Phe4Cys] and c.97C>T [p.Arg33Trp]) in AP1S3, the gene encoding AP-1 complex subunit σ1C, in 15 unrelated individuals with a severe autoinflammatory skin disorder known as pustular psoriasis. Because the variants are predicted to destabilize the 3D structure of the AP-1 complex, we generated AP1S3-knockdown cell lines to investigate the consequences of AP-1 deficiency in skin keratinocytes. We found that AP1S3 silencing disrupted the endosomal translocation of the innate pattern-recognition receptor TLR-3 (Toll-like Receptor 3) and resulted in a marked inhibition of downstream signaling. These findings identify pustular psoriasis as an autoinflammatory phenotype caused by defects in vesicular trafficking and demonstrate a requirement of AP-1 for Toll-like Receptor homeostasis.

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