@article{WiesslerTalucciPiroetal.2024, author = {Wiessler, Anna-Lena and Talucci, Ivan and Piro, Inken and Seefried, Sabine and H{\"o}rlin, Verena and Baykan, Bet{\"u}l B. and T{\"u}z{\"u}n, Erdem and Schaefer, Natascha and Maric, Hans M. and Sommer, Claudia and Villmann, Carmen}, title = {Glycine receptor β-targeting autoantibodies contribute to the pathology of autoimmune diseases}, series = {Neurology: Neuroimmunology \& Neuroinflammation}, volume = {11}, journal = {Neurology: Neuroimmunology \& Neuroinflammation}, number = {2}, doi = {10.1212/NXI.0000000000200187}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-349958}, year = {2024}, abstract = {Background and Objectives Stiff-person syndrome (SPS) and progressive encephalomyelitis with rigidity and myoclonus (PERM) are rare neurologic disorders of the CNS. Until now, exclusive GlyRα subunit-binding autoantibodies with subsequent changes in function and surface numbers were reported. GlyR autoantibodies have also been described in patients with focal epilepsy. Autoimmune reactivity against the GlyRβ subunits has not yet been shown. Autoantibodies against GlyRα1 target the large extracellular N-terminal domain. This domain shares a high degree of sequence homology with GlyRβ making it not unlikely that GlyRβ-specific autoantibody (aAb) exist and contribute to the disease pathology. Methods In this study, we investigated serum samples from 58 patients for aAb specifically detecting GlyRβ. Studies in microarray format, cell-based assays, and primary spinal cord neurons and spinal cord tissue immunohistochemistry were performed to determine specific GlyRβ binding and define aAb binding to distinct protein regions. Preadsorption approaches of aAbs using living cells and the purified extracellular receptor domain were further used. Finally, functional consequences for inhibitory neurotransmission upon GlyRβ aAb binding were resolved by whole-cell patch-clamp recordings. Results Among 58 samples investigated, cell-based assays, tissue analysis, and preadsorption approaches revealed 2 patients with high specificity for GlyRβ aAb. Quantitative protein cluster analysis demonstrated aAb binding to synaptic GlyRβ colocalized with the scaffold protein gephyrin independent of the presence of GlyRα1. At the functional level, binding of GlyRβ aAb from both patients to its target impair glycine efficacy. Discussion Our study establishes GlyRβ as novel target of aAb in patients with SPS/PERM. In contrast to exclusively GlyRα1-positive sera, which alter glycine potency, aAbs against GlyRβ impair receptor efficacy for the neurotransmitter glycine. Imaging and functional analyses showed that GlyRβ aAbs antagonize inhibitory neurotransmission by affecting receptor function rather than localization.}, language = {en} } @article{Prieto‐GarciaHartmannReisslandetal.2020, author = {Prieto-Garcia, Cristian and Hartmann, Oliver and Reissland, Michaela and Braun, Fabian and Fischer, Thomas and Walz, Susanne and Sch{\"u}lein-V{\"o}lk, Christina and Eilers, Ursula and Ade, Carsten P. and Calzado, Marco A. and Orian, Amir and Maric, Hans M. and M{\"u}nch, Christian and Rosenfeldt, Mathias and Eilers, Martin and Diefenbacher, Markus E.}, title = {Maintaining protein stability of ∆Np63 via USP28 is required by squamous cancer cells}, series = {EMBO Molecular Medicine}, volume = {12}, journal = {EMBO Molecular Medicine}, number = {4}, doi = {10.15252/emmm.201911101}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218303}, year = {2020}, abstract = {The transcription factor ∆Np63 is a master regulator of epithelial cell identity and essential for the survival of squamous cell carcinoma (SCC) of lung, head and neck, oesophagus, cervix and skin. Here, we report that the deubiquitylase USP28 stabilizes ∆Np63 and maintains elevated ∆NP63 levels in SCC by counteracting its proteasome-mediated degradation. Impaired USP28 activity, either genetically or pharmacologically, abrogates the transcriptional identity and suppresses growth and survival of human SCC cells. CRISPR/Cas9-engineered in vivo mouse models establish that endogenous USP28 is strictly required for both induction and maintenance of lung SCC. Our data strongly suggest that targeting ∆Np63 abundance via inhibition of USP28 is a promising strategy for the treatment of SCC tumours.}, language = {en} }