Figure 1.

Schematic of how palmitate induces mitochondrial fragmentation in pancreatic β-cells. Palmitate activates NOX-2 (NADPH oxidase-2) to induce ROS (reactive oxygen species) production. ROS activates TRPM2 channel leading to extracellular Ca²⁺ (purple dots) entry, and Ca²⁺-induced lysosomal Zn²⁺ (blue dots) transfer to mitochondria. Rise in mitochondrial Zn²⁺ induces Drp1 (red dots) recruitment, breakdown of the mitochondrial network and eventually β-cell death.