Professor Dr. Jochen Walter

Department of Neurology
– Molecular Cell Biology –
University of Bonn Medical Center
Sigmund-Freud-Str. 25
D- 53127 Bonn

Phone +49 (0) 228 287-19782
Fax +49 (0) 228 287-14387
Jochen.Walter@ukb.uni-bonn.de

Website

Curriculum vitae Professor Dr. Jochen Walter

Research Interests

Alzheimer’s disease (AD) is the most common form of dementia and characterized at the neuropathological level by the combined occurrence of intraneuronal aggregates of the microtubule associated protein tau and extracellular ß-amyloid plaques.

We are interested in molecular and cellular mechanisms involved in the pathogenesis of AD. Our research is focused on the understanding of intra- and intercellular signaling pathways that contribute to Alzheimer-associated neurodegeneration. In particular, we try to dissect the metabolism of the amyloid ß-peptide, its post-translational modifications and aggregation. Another line of research addresses of the role of membrane lipids in the subcellular transport and activity of disease-related proteins. The overarching aim is to provide better insight into the pathogenesis of AD that could help to develop strategies for prevention and therapy, and identify targets for molecular diagnosis and differentiation of this disease.

Techniques

Experimental models and methods

To address our scientific questions, we employ different experimental systems, including cell free, cellular and in vivo models (mice, flies) and apply standard and advanced biochemical, molecular cell biological, and histochemical methods.

Biochemistry:
Protein extraction and purification, Western immunoblotting, photometry, immunoprecipitation, immunoisolation, cell fractionation, real-time spectrometry, live-cell metabolic labelling, autoradiography, ECL and fluorescence imaging, histochemisty.

Molecular biology: 
real-time PCR, genome editing, RNA interference, DNA mutagenesis, molecular cloning, yeast two hybrid.

Cell biology: 
live cell imaging, fluorescence microscopy, immunocytochemistry, primary cell cultures, transfection, single cell cloning, Ca2+ imaging, cell migration assays.

5 most important publications

1. Kumar S, Wirths O, Stüber K, Wunderlich P, Koch P, Theil S, Rezaei-Ghaleh N, Zweckstetter M, Bayer TA, Brüstle O, Thal DR, Walter J. (2016) Phosphorylation of the amyloid â-peptide at Ser26 stabilizes oligomeric assembly and increases neurotoxicity. Acta Neuropathol, 131: 525-437.

2. Glebov K, Löchner M, Jabs R, Lau T, Merkel O, Schloss P, Steinhäuser C, Walter J. (2015) Serotonin stimulates secretion of exosomes from microglia cells. GLIA, 63: 626-634.

3. Wunderlich P, Glebov K, Kemmerling N, Tien NT, Neumann H, Walter J. (2013) Sequential proteolytic processing of the triggering receptor expressed on myeloid cells-2 (TREM2) by ectodomain shedding and ã-secretase dependent intramembranous cleavage. J Biol Chem, 288: 33027–33036.

4. Kumar S, Rezaei-Ghaleh N, Terwel D, Thal DR, Richard M, Hoch M, Mc Donald JM, Wüllner U, Glebov K, Heneka MT, Walsh DM, Zweckstetter M, Walter J. (2011) Extracellular phosphorylation of the amyloid ß-peptide promotes formation of toxic aggregates during the pathogenesis of Alzheimer’s disease. EMBO J, 30: 2255-2265.

5. Tamboli IY, Barth E, Christian L, Siepmann M, Singh S, Kumar S, Tolksdorf K, Heneka MT, Lütjohann D, Wunderlich P, Walter J. (2010) Statins promote the degradation of extracellular amyloid b-peptide by microglia via stimulation of exosome-associated IDE secretion. J Biol Chem, 285: 37405-37414.