title: New mechanism of X-linked anhidrotic ectodermal dysplasia with immunodeficiency: impairment of ubiquitin binding despite normal folding of NEMO protein.
abstract: Nuclear factor-κB essential modulator (NEMO), the regulatory subunit of the IκB kinase complex, is a critical component of the NF-κB pathway. Hypomorphic mutations in the X-linked human NEMO gene cause various forms of anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID). All known X-linked EDA-ID-causing mutations impair NEMO protein expression, folding, or both. We describe here 2 EDA-ID-causing missense mutations that affect the same residue in the CC2-LZ domain (D311N and D311G) that do not impair NEMO production or folding. Structural studies based on pull-down experiments showed a defect in noncovalent interaction with K63-linked and linear polyubiquitin chains for these mutant proteins. Functional studies on the patients' cells showed an impairment of the classic NF-κB signaling pathways after activation of 2 NEMO ubiquitin-binding-dependent receptors, the TNF and IL-1β receptors, and in the CD40-dependent NF-κB pathway. We report the first human NEMO mutations responsible for X-linked EDA-ID found to affect the polyubiquitin binding of NEMO rather than its expression and folding. These experiments demonstrate that the binding of human NEMO to polyubiquitin is essential for NF-κB activation. They also demonstrate that the normal expression and folding of NEMO do not exclude a pathogenic role for NEMO mutations in patients with EDA-ID.
authors.affiliation: Laboratory of Human Genetics of Infectious Diseases, Necker Branch, Inserm, U980, Paris, France.
authors.forename: Marjorie
authors.initials: M
authors.lastname: Hubeau
authors.forename: Flora
authors.initials: F
authors.lastname: Ngadjeua
authors.forename: Anne
authors.initials: A
authors.lastname: Puel
authors.forename: Laura
authors.initials: L
authors.lastname: Israel
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Feinberg
authors.forename: Maya
authors.initials: M
authors.lastname: Chrabieh
authors.forename: Kiran
authors.initials: K
authors.lastname: Belani
authors.forename: Christine
authors.initials: C
authors.lastname: Bodemer
authors.forename: Isabelle
authors.initials: I
authors.lastname: Fabre
authors.forename: Alessandro
authors.initials: A
authors.lastname: Plebani
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Boisson-Dupuis
authors.forename: Capucine
authors.initials: C
authors.lastname: Picard
authors.forename: Alain
authors.initials: A
authors.lastname: Fischer
authors.forename: Alain
authors.initials: A
authors.lastname: Israel
authors.forename: Laurent
authors.initials: L
authors.lastname: Abel
authors.forename: Michel
authors.initials: M
authors.lastname: Veron
authors.forename: Jean-Laurent
authors.initials: JL
authors.lastname: Casanova
authors.forename: Fabrice
authors.initials: F
authors.lastname: Agou
authors.forename: Jacinta
authors.initials: J
authors.lastname: Bustamante
mesh_terms: D015153:Blotting, Western; D053358:Ectodermal Dysplasia 1, Anhidrotic / Q000235:genetics* / Q000378:metabolism; D004789:Enzyme Activation / Q000235:genetics; D005260:Female; D006801:Humans; D051550:I-kappa B Kinase / Q000235:genetics* / Q000378:metabolism; D007153:Immunologic Deficiency Syndromes / Q000235:genetics* / Q000378:metabolism; D008297:Male; D020125:Mutation, Missense; D016328:NF-kappa B / Q000378:metabolism; D010375:Pedigree; D011485:Protein Binding; D017510:Protein Folding; D015398:Signal Transduction / Q000235:genetics; D025801:Ubiquitin / Q000378:metabolism*; D055815:Young Adult
chemical_list: C491731:IKBKG protein, human; D016328:NF-kappa B; D025801:Ubiquitin; D051550:I-kappa B Kinase