Dieter Edbauer is professor of translational neurobiochemistry at Ludwig Maximilian University in Munich, Germany. He is co-leading the project Frontotemporal Lobar Degeneration—from the Basic Mechanism and Target Identification to Translational and Clinical Approaches. 

Edbauer received his MD from the University of Munich (LMU; Germany) in 2001. In his doctoral thesis with M. Hallek at the gene center of LMU, he investigated using DNA vaccines against lymphomas (1998-2001). As a medical intern (AiP), later as a postdoc and then as a research assistant, he moved to the Adolf Butenandt Institute at LMU, where he and Christian Haass researched the biochemical mechanisms of Alzheimer‘s disease (2001-2004). As part of their work, a key enzyme in Alzheimer‘s disease, the so-called gamma secretase, was molecularly defined for the first time. This was followed by a stay abroad at the Massachusetts Institute of Technology in the laboratory of M. Sheng (2004-2009). There, his work focused on signal transduction and cell biology in neurons in connection with Alzheimer‘s and Fragile X Syndrome, a hereditary form of mental retardation. In November 2009, Edbauer returned to the newly founded DZNE in Munich as the first Helmholtz Young Investigator Group Leader.

Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are fatal neurodegenerative diseases with overlapping genetics and pathology. The most common cause is expansion of a (GGGGCC)n repeat in the first intron of the gene C9orf72. Edbauer and colleagues discovered that the repeat region is translated in all reading frames into aggregating dipeptide-repeat (DPR) proteins (poly-GA, -GP, -GR, -PA and -PR) despite its intronic localization and lack of an ATG start codon. They are now analyzing the role of DPR proteins in pathogenesis from the ultrastructural to patient level in order to inhibit DPR synthesis and/or toxicity and thus prevent or treat C9orf72 ALS/FTD. Their cellular models show that DPR aggregates sequester key cellular proteins leading to toxicity. The hydrophobic DPR proteins poly-GA, -GP and -PA are transmitted between cells. Since antibodies inhibit poly-GA uptake and aggregation in vitro, Edbauer and team are testing immunotherapy in mouse models. Using immunoassays, they detected poly-GP in the CSF of C9orf72 ALS and FTD patients. Surprisingly, poly-GP levels are similar in presymptomatic and symptomatic C9orf72 carriers, indicating that DPR proteins play an early role in pathogenesis and may trigger TDP-43 pathology and neurodegeneration in a cascade-like mechanism.

Edbauer is dissecting C9orf72 pathogenesis further using primary neuron culture, mouse models (with B. Wefers, DZNE Munich), proteomics (with F. Meißner and M. Mann, MPI Martinsried) and cryo-electron tomography (with R. Fernandez-Busnadiego and W. Baumeister, MPI Martinsried). Whenever possible, they use human brain tissue to confirm their in vitro in patients (with T. Arzberger, DZNE Munich). Using cellular assays, the team aims to understand the mechanisms of the unusual translation of the expanded C9orf72 repeat to develop inhibitors for future therapy.