Sirtuin-1 sensitive lysine-136 acetylation drives phase separation and pathological aggregation of TDP-43

• Published in: Nature communications 2022-03, Vol.13 (1), p.1223-1223, Article 1223
• Main Authors: Garcia Morato, Jorge, Hans, Friederike, von Zweydorf, Felix, Feederle, Regina, Elsässer, Simon J., Skodras, Angelos A., Gloeckner, Christian Johannes, Buratti, Emanuele, Neumann, Manuela, Kahle, Philipp J.
• Format: Article
• Language: English
• Subjects: 13; 13/1; 13/109; 14/63; 631/337/1645/1792; 631/80/304; 631/80/389/2023; 631/80/458/1275; 692/617/375/1917/1285; 82/29; Acetylation; Agglomeration; Aggregates; Amyotrophic lateral sclerosis; Amyotrophic Lateral Sclerosis - metabolism; Antibodies; Degeneration; DNA-binding protein; DNA-Binding Proteins - metabolism; Frontotemporal dementia; Humanities and Social Sciences; Humans; Imports; Localization; Lysine; Lysine - metabolism; multidisciplinary; Neuropathology; Nuclear transport; Nucleic acids; Pathogenesis; Phase separation; Post-translation; Protein Aggregation, Pathological - metabolism; Protein Processing, Post-Translational; Proteins; Regulatory mechanisms (biology); Ribonucleic acid; RNA; RNA - metabolism; RNA processing; RNA transport; Science; Science (multidisciplinary); Sirtuin 1 - genetics; Sirtuin 1 - metabolism; Site-directed mutagenesis; Splicing; Translation
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-28822-7

Trans-activation response DNA-binding protein of 43  kDa (TDP-43) regulates RNA processing and forms neuropathological aggregates in patients with amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Investigating TDP-43 post-translational modifications, we discovered that K84 acetylation reduced nuclear import whereas K136 acetylation impaired RNA binding and splicing capabilities of TDP-43. Such failure of RNA interaction triggered TDP-43 phase separation mediated by the C-terminal low complexity domain, leading to the formation of insoluble aggregates with pathologically phosphorylated and ubiquitinated TDP-43. Introduction of acetyl-lysine at the identified sites via amber suppression confirmed the results from site-directed mutagenesis. K84-acetylated TDP-43 showed cytoplasmic mislocalization, and the aggregation propensity of K136-acetylated TDP-43 was confirmed. We generated antibodies selective for TDP-43 acetylated at these lysines, and found that sirtuin-1 can potently deacetylate K136-acetylated TDP-43 and reduce its aggregation propensity. Thus, distinct lysine acetylations modulate nuclear import, RNA binding and phase separation of TDP-43, suggesting regulatory mechanisms for TDP-43 pathogenesis. TDP-43 is a nucleic acid binding protein, whose insoluble aggregates are neuropathological hallmarks of specific subsets of patients with amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Post-translational modifications and acetylation of TDP-43 impact its interaction with RNA, its localization in the cells, and are linked to disease. Using antibodies generated against TDP-43 lysine acetylation sites, sirtuin-1 was found to potently deacetylate amber suppressed [acK136]TDP-43 and reduce its aggregation propensity. Thus, distinct lysine acetylations modulate nuclear import, RNA binding as well as phase separation and aggregation of TDP-43, suggesting regulatory mechanisms for TDP-43 pathogenesis.