Researchers resolve a dynamic diffusion barrier at mitochondrial crista entrances

An open-access Nature Communications study published September 26 examines mitochondrial crista junctions, narrow gateways that separate inner-membrane folds and their tuned protein, metabolite and ion environment. The team determined the crystal structure of an amino-terminal dimeric helical bundle of human Mic60, then combined structural and biochemical evidence, in-organello and in-vitro cross-linking, and molecular-dynamics simulations to build a dynamic model of the tetrameric Mic60-Mic19 subcomplex spanning the junction. The model supports a diffusion-barrier function while accommodating the movement of a flexible multi-domain complex. This is peer-reviewed structural and computational mechanism, not a human therapeutic result. Its immediate value is a way to investigate flexible protein machines that conventional structural methods struggle to capture; disease relevance still requires further experiments.