Amyloid Precursor Protein dependent generation of nuclear complexes in gene edited iPSC derived neurons
Molecular Biology and Physiology of Neurons and Glial Cells
Final Report Abstract
Our research, funded by the German Research Foundation (DFG), has provided significant insights into the role of the amyloid precursor protein (APP) in Alzheimer's disease and the application of CRISPR/Cas9 technology for studying genetic processes in the brain. These findings contribute to a better understanding of the underlying mechanisms of neurodegenerative diseases and support the development of new experimental approaches. APP is a protein found in nerve cells that has been linked to the development of Alzheimer's disease. Our research indicates that APP plays a crucial role in the fusion of so called promyelocytic leukemia nuclear bodies (PML-NBs) in brain regions with high levels of Alzheimerspecific plaques. These cellular structures are involved in regulating gene expression and can influence the stability of cellular functions. Notably, a specific form of APP, known as APP-CT50, directly interacts with key tumor suppressor proteins such as p53 and PML. This interaction triggers processes related to cellular aging and may contribute to the progression of neurodegenerative diseases. While these protective mechanisms are still present in healthy and aging brains, they appear significantly reduced in Alzheimer's brains, suggesting that APP- CT50 may be a key factor in disease development. In addition to studying APP, we employ advanced genetic technologies such as CRISPR/Cas9 to investigate brain processes in a targeted manner. A key aspect of our research was the creation of cerebral organoids—small, stem cell-derived brain models that mimic complex cellular interactions. By fusing fluorescent proteins with specific cellular structure proteins, we were able to visualize different cell populations within these organoids and genetically modify them. This approach enables precise analysis of biological processes essential for brain function. A particularly innovative aspect was the combination of different cell lines (derived from two different stem cell lines) within a single organoid, allowing direct comparisons between genetically modified and control cells. This method minimizes variability between individual organoids and significantly improves data reliability. Our findings highlight the critical interactions between APP and cellular structures in the pathology of Alzheimer's disease and demonstrate that genetic model systems such as CRISPR/Cas9 can enhance our understanding of these mechanisms. The insights gained from our research open new avenues for the development of experimental therapies and preclinical models for studying neurodegenerative diseases. In the long term, this could lead to improved treatment options for Alzheimer's disease and other neurological disorders.
Publications
-
Amyloid precursor protein elevates fusion of promyelocytic leukemia nuclear bodies in human hippocampal areas with high plaque load. Acta Neuropathologica Communications, 9(1).
Marks, David; Heinen, Natalie; Bachmann, Lisa; Meermeyer, Sophia; Werner, Michelle; Gallego, Lucia; Hemmerich, Peter; Bader, Verian; Winklhofer, Konstanze F.; Schröder, Elisabeth; Knauer, Shirley K. & Müller, Thorsten
-
Gene-Edited Fluorescent and Mixed Cerebral Organoids. The CRISPR Journal, 5(1), 53-65.
Bachmann, Lisa; Gallego Villarejo, Lucia; Heinen, Natalie; Marks, David; Peters, Marcus & Müller, Thorsten
-
Role of Intracellular Amyloid β as Pathway Modulator, Biomarker, and Therapy Target. International Journal of Molecular Sciences, 23(9), 4656.
Gallego Villarejo, Lucia; Bachmann, Lisa; Marks, David; Brachthäuser, Maite; Geidies, Alexander & Müller, Thorsten
