Elucidating the Allosteric Mechanisms in Human AMPK Through High-Resolution Cryo-EM Studies

The allosteric regulation of AMP-activated protein kinase (AMPK) plays a pivotal role in cellular energy homeostasis, making it a critical target for therapeutic intervention in metabolic disorders. Despite extensive study, the detailed structural mechanisms underlying its allosteric modulation remain obscure. This study aims to delineate the molecular basis of AMPK regulation using cutting-edge cryo-electron microscopy (cryo-EM) at near-atomic resolution. We employed cryo-EM to capture the AMPK holoenzyme in different conformational states, supplemented by molecular dynamics simulations to explore its dynamic landscape. Our findings reveal substantial conformational changes between the active and inactive states, highlighting key interdomain interactions and novel phosphorylation sites. Notably, the allosteric activation by AMP results in a 35% increase in the accessibility of critical catalytic residues, as quantified through solvent accessibility surface area calculations. Additionally, we identified a new binding interface that stabilizes the active conformation, providing potential targets for drug design. The study not only advances our understanding of AMPK's structure-function relationship but also sets the stage for the development of allosteric modulators with improved specificity and efficacy. These insights could have significant implications for therapeutic strategies targeting metabolic diseases.