title: A20 and CYLD do not share significant overlapping functions during B cell development and activation.
abstract: The ubiquitin-editing enzyme A20 (TNFAIP3) and the deubiquitinase CYLD are central negative regulators of NF-κB signaling. Both can act by removing nonproteolytic K63-linked polyubiquitin chains from an overlapping set of signaling molecules. In B cells, A20 deficiency results in hyperactivity, loss of immune homeostasis, inflammation, and autoimmunity. The reported consequences of CYLD deficiency are controversial, ranging from an absence of effects to dramatic B cell hyperplasia. These differences could be due to varying compensation for the loss of CYLD function by A20. Therefore, to explore potential overlapping physiological functions between A20 and CYLD, we generated and characterized A20/CYLD double-deficient B cells. Interestingly, the lack of both A20 and CYLD did not exacerbate the developmental defects and hyperresponsive activity of A20-deficient B cells. In addition, the extent of B cell activation after in vitro stimulation with anti-CD40, LPS, and CpG was comparable in B cells lacking A20/CYLD and A20 alone. However, in response to BCR cross-linking, we observed small but reproducible additive effects of the lack of A20 and CYLD. Taken together, our results demonstrate that A20 and CYLD do not share significant functions during B cell development and activation.
authors.affiliation: Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Chu
authors.forename: Valeria
authors.initials: V
authors.lastname: Soberon
authors.forename: Laura
authors.initials: L
authors.lastname: Glockner
authors.forename: Rudi
authors.initials: R
authors.lastname: Beyaert
authors.forename: Ramin
authors.initials: R
authors.lastname: Massoumi
authors.forename: Geert
authors.initials: G
authors.lastname: van Loo
authors.forename: Daniel
authors.initials: D
authors.lastname: Krappmann
authors.forename: Marc
authors.initials: M
authors.lastname: Schmidt-Supprian
mesh_terms: D000818:Animals; D016175:B-Lymphocyte Subsets / Q000201:enzymology / Q000276:immunology* / Q000378:metabolism*; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology*; D003546:Cysteine Endopeptidases / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D000074749:Deubiquitinating Enzyme CYLD; D005807:Genes, Overlapping / Q000276:immunology; D047908:Intracellular Signaling Peptides and Proteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3; D044767:Ubiquitin-Protein Ligases / Q000172:deficiency / Q000235:genetics / Q000502:physiology*
chemical_list: D004268:DNA-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; D044767:Ubiquitin-Protein Ligases; C511601:CYLD protein, mouse; D000074749:Deubiquitinating Enzyme CYLD; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3; D003546:Cysteine Endopeptidases; C513261:Tnfaip3 protein, mouse