Quantitative Assessment of Mitochondrial Volumetric Transitions in Arabidopsis thaliana.

Mitochondria in plants typically appear as discrete spherical or slightly tubular organelles, with their morphology and volume serving as indicators of metabolic state and dysfunction. Measuring changes in mitochondrial volume is relatively straightforward in organisms lacking plastids. However, in chlorophyll-rich tissues, such assessments often require purification protocols that may compromise accuracy. Here, we present protocols for the quantitative assessment of mitochondrial volume transitions in leaf mesophyll cells of Arabidopsis thaliana. The methods are simple and highly sensitive and offer a reliable approach for studying mitochondrial morphology transitions under both physiological and stress conditions. © 2025 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Leaf mesophyll treatment and mitochondrial imaging Basic Protocol 2: Leaf mesophyll mitochondrial volume assessment Basic Protocol 3: Mitochondrial volume statistics.