The AMP-activated protein kinase (AMPK) is a master metabolic regulator and energy sensor that has been extensively studied in the context of cancer and metabolic disorders. However, its role in neuronal function and morphology remains largely unexplored. This dissertation aims to bridge this gap by investigating the roles of AMPK in maintaining axon homeostasis and regulating mitochondrial morphology in neurons. By identifying novel regulators of AMPK across different cellular compartments, this thesis sheds light on the multifaceted functions of AMPK in shaping neuronal and mitochondrial architecture.
The dissertation is organized into five chapters. Chapter 1 provides a brief background on AMPK, its activation mechanisms, and the downstream pathways it regulates. Chapter 2 introduces with-no-lysine kinase (WNK), a novel axon morphogenic kinase with dual roles in terminal axon branch development and maintenance in mature axons. Chapter 3 investigates the role of AMPK in mediating the loss-of-WNK axonal phenotypes, revealing a critical link between AMPK and axonal integrity. Chapter 4 shifts focus to the mitochondrial, characterizing mitochondrial fission regulator 1-like (MTFR1L) as a novel AMPK-activated protein that regulates mitochondrial morphology.
Finally, Chapter 5 explores the role of AMPK in mediating activity-dependent mitochondrial morphology in hippocampal CA1 neurons, highlighting the dynamic interplay between neuronal activity and mitochondrial dynamics. Collectively, these findings provide novel insights into the multifaceted roles of AMPK in neuronal development, degeneration, and organelle regulation, underscoring the importance of this master kinase in maintaining neuronal health and homeostasis
