MCM3AP and POMP Mutations Cause a DNA-Repair and DNA-Damage-Signaling Defect in an Immunodeficient Child.

Abstract

Immunodeficiency patients with DNA repair defects exhibit radiosensitivity and proneness to leukemia/lymphoma formation. Though progress has been made in identifying the underlying mutations, in most patients the genetic basis is unknown. Two de novo mutated candidate genes, MCM3AP encoding germinal center-associated nuclear protein (GANP) and POMP encoding proteasome maturation protein (POMP), were identified by whole-exome sequencing (WES) and confirmed by Sanger sequencing in a child with complex phenotype displaying immunodeficiency, genomic instability, skin changes, and myelodysplasia. GANP was previously described to promote B-cell maturation by nuclear targeting of activation-induced cytidine deaminase (AID) and to control AID-dependent hyperrecombination. POMP is required for 20S proteasome assembly and, thus, for efficient NF-κB signaling. Patient-derived cells were characterized by impaired homologous recombination, moderate radio- and cross-linker sensitivity associated with accumulation of damage, impaired DNA damage-induced NF-κB signaling, and reduced nuclear AID levels. Complementation by wild-type (WT)-GANP normalized DNA repair and WT-POMP rescued defective NF-κB signaling. In conclusion, we identified for the first time mutations in MCM3AP and POMP in an immunodeficiency patient. These mutations lead to cooperative effects on DNA recombination and damage signaling. Digenic/polygenic mutations may constitute a novel genetic basis in immunodeficiency patients with DNA repair defects.

• Authors: Susanne A Gatz, Daniela Salles, Eva-Maria Jacobsen, Thilo Dörk, Tobias Rausch, Sevtap Aydin, Harald Surowy, Meta Volcic, Walther Vogel, Klaus-Michael Debatin, Adrian M Stütz, Klaus Schwarz, Ulrich Pannicke, Timo Hess, Jan O Korbel, Ansgar S Schulz, Johannes Schumacher, Lisa Wiesmüller
• Journal: Human mutation (Hum Mutat) Vol. 37 Issue 3 Pg. 257-68 (Mar 2016) ISSN: 1098-1004 [Electronic] United States
• PMID: 26615982 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 WILEY PERIODICALS, INC.

Chemical References

• Intracellular Signaling Peptides and Proteins
• Molecular Chaperones
• proteasome maturation protein
• Acetyltransferases
• MCM3AP protein, human

Topics

• Acetyltransferases (genetics)
• DNA Damage (genetics, physiology)
• DNA Repair (genetics, physiology)
• Humans
• Immunologic Deficiency Syndromes (genetics)
• Intracellular Signaling Peptides and Proteins (genetics)
• Molecular Chaperones (genetics)
• Mutation (genetics)
• Signal Transduction (genetics, physiology)