@article{HornburgDrepperButteretal.2014, author = {Hornburg, Daniel and Drepper, Carsten and Butter, Falk and Meissner, Felix and Sendtner, Michael and Mann, Matthias}, title = {Deep Proteomic Evaluation of Primary and Cell Line Motoneuron Disease Models Delineates Major Differences in Neuronal Characteristics*}, series = {Molecular \& Cellular Proteomics : MCP}, volume = {13}, journal = {Molecular \& Cellular Proteomics : MCP}, number = {12}, issn = {1535-9484}, doi = {10.1074/mcp.M113.037291}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120954}, pages = {3410-20}, year = {2014}, abstract = {The fatal neurodegenerative disorders amyotrophic lateral sclerosis and spinal muscular atrophy are, respectively, the most common motoneuron disease and genetic cause of infant death. Various in vitro model systems have been established to investigate motoneuron disease mechanisms, in particular immortalized cell lines and primary neurons. Using quantitative mass-spectrometry-based proteomics, we compared the proteomes of primary motoneurons to motoneuron-like cell lines NSC-34 and N2a, as well as to non-neuronal control cells, at a depth of 10,000 proteins. We used this resource to evaluate the suitability of murine in vitro model systems for cell biological and biochemical analysis of motoneuron disease mechanisms. Individual protein and pathway analysis indicated substantial differences between motoneuron-like cell lines and primary motoneurons, especially for proteins involved in differentiation, cytoskeleton, and receptor signaling, whereas common metabolic pathways were more similar. The proteins associated with amyotrophic lateral sclerosis also showed distinct differences between cell lines and primary motoneurons, providing a molecular basis for understanding fundamental alterations between cell lines and neurons with respect to neuronal pathways with relevance for disease mechanisms. Our study provides a proteomics resource for motoneuron research and presents a paradigm of how mass-spectrometry-based proteomics can be used to evaluate disease model systems.}, language = {en} } @article{GhanawiHennleinZareetal.2021, author = {Ghanawi, Hanaa and Hennlein, Luisa and Zare, Abdolhossein and Bader, Jakob and Salehi, Saeede and Hornburg, Daniel and Ji, Changhe and Sivadasan, Rajeeve and Drepper, Carsten and Meissner, Felix and Mann, Matthias and Jablonka, Sibylle and Briese, Michael and Sendtner, Michael}, title = {Loss of full-length hnRNP R isoform impairs DNA damage response in motoneurons by inhibiting Yb1 recruitment to chromatin}, series = {Nucleic Acids Research}, volume = {49}, journal = {Nucleic Acids Research}, number = {21}, doi = {10.1093/nar/gkab1120}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265687}, pages = {12284-12305}, year = {2021}, abstract = {Neurons critically rely on the functions of RNA-binding proteins to maintain their polarity and resistance to neurotoxic stress. HnRNP R has a diverse range of post-transcriptional regulatory functions and is important for neuronal development by regulating axon growth. Hnrnpr pre-mRNA undergoes alternative splicing giving rise to a full-length protein and a shorter isoform lacking its N-terminal acidic domain. To investigate functions selectively associated with the full-length hnRNP R isoform, we generated a Hnrnpr knockout mouse (Hnrnpr\(^{tm1a/tm1a}\)) in which expression of full-length hnRNP R was abolished while production of the truncated hnRNP R isoform was retained. Motoneurons cultured from Hnrnpr\(^{tm1a/tm1a}\) mice did not show any axonal growth defects but exhibited enhanced accumulation of double-strand breaks and an impaired DNA damage response upon exposure to genotoxic agents. Proteomic analysis of the hnRNP R interactome revealed the multifunctional protein Yb1 as a top interactor. Yb1-depleted motoneurons were defective in DNA damage repair. We show that Yb1 is recruited to chromatin upon DNA damage where it interacts with gamma-H2AX, a mechanism that is dependent on full-length hnRNP R. Our findings thus suggest a novel role of hnRNP R in maintaining genomic integrity and highlight the function of its N-terminal acidic domain in this context.}, language = {en} } @article{JiBaderRamanathanetal.2021, author = {Ji, Changhe and Bader, Jakob and Ramanathan, Pradhipa and Hennlein, Luisa and Meissner, Felix and Jablonka, Sibylle and Mann, Matthias and Fischer, Utz and Sendtner, Michael and Briese, Michael}, title = {Interaction of 7SK with the Smn complex modulates snRNP production}, series = {Nature Communications}, volume = {12}, journal = {Nature Communications}, number = {1}, doi = {10.1038/s41467-021-21529-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259125}, pages = {1278}, year = {2021}, abstract = {Gene expression requires tight coordination of the molecular machineries that mediate transcription and splicing. While the interplay between transcription kinetics and spliceosome fidelity has been investigated before, less is known about mechanisms regulating the assembly of the spliceosomal machinery in response to transcription changes. Here, we report an association of the Smn complex, which mediates spliceosomal snRNP biogenesis, with the 7SK complex involved in transcriptional regulation. We found that Smn interacts with the 7SK core components Larp7 and Mepce and specifically associates with 7SK subcomplexes containing hnRNP R. The association between Smn and 7SK complexes is enhanced upon transcriptional inhibition leading to reduced production of snRNPs. Taken together, our findings reveal a functional association of Smn and 7SK complexes that is governed by global changes in transcription. Thus, in addition to its canonical nuclear role in transcriptional regulation, 7SK has cytosolic functions in fine-tuning spliceosome production according to transcriptional demand.}, language = {en} }