Local Mitochondrial Growth Initiated by Femtosecond Laser-Evoked Ca2+ Signaling

Mitochondrial structural remodeling is closely coupled to intracellular CA²⁺ signaling, and precise spatiotemporal control of this process is critical for understanding mitochondrial physiology. Here, we report an optical approach based on femtoSOC (femtosecond laser-controlled store-operated Calcium Channel) activation to induce localized CA²⁺ influx and trigger region-specific mitochondrial growth in living cells. The CA²⁺-regulated mitochondrial growth relies on MCU-dependent CA²⁺ uptake and OPA1-mediated fusion but is not primarily mediated by the AMPK/CaMKKβ pathway. This study provides a minimally invasive strategy for precise optical control of mitochondrial dynamics and reveals an AMPK-distinct pathway linking localized CA²⁺ signaling to mitochondrial structural remodeling.