Approaches and Application Examples for Studying Mitochondrial Morphology and Function in Caenorhabditis elegans

doi:10.12300/j.issn.1674-5817.2025.119

Abstract

Abstract:

Mitochondria, as the energy metabolism center of cells, have abnormal dynamic morphology and oxidative phosphorylation function, which are directly related to aging and various diseases. Caenorhabditis elegans (C. elegans) is a widely used model animal. This article systematically summarizes the experimental methods for analyzing mitochondrial morphology and function at multiple scales in the laboratory using C. elegans as a model, mainly including: (1) morphological qualitative analysis, which uses a single-blind manual classification method (such as point, rod, and mesh), although it relies on subjective experience, it is easy to operate and suitable for preliminary phenotype screening; (2) morphological quantitative analysis, which relies on the Fiji/ImageJ platform for automated parameter extraction of mitochondria in specific tissues (such as epidermis and body wall muscles), quantifies network connectivity (number of branch points, network length) through skeletonization algorithm, and calculates fragmentation indices (such as area/perimeter ratio, fragment count) with binarization analysis, achieving objective phenotype comparison; (3) high-throughput image processing, which performs batch processing through macro commands, integrates morphological filtering, threshold segmentation, and parameter export workflow, significantly improving research efficiency for large sample sizes; (4) metabolic function monitoring, which uses the Seahorse XF analyzer to measure in vivo respiratory metabolism in C. elegans. By sequential injection of ATP synthase inhibitor N, N'-dicyclohexylcarbodiimide (DCCD), uncoupling agent carbonyl cyanide-4-(trifluoromethoxy) phenylhydrazone (FCCP) and respiratory chain inhibitor sodium azide (NaN3), the basal oxygen consumption rate (OCR), ATP coupled respiratory efficiency, and maximum respiratory capacity (respiratory potential) are accurately analyzed to reveal energy metabolism patterns. This article integrates a dual dimensional approach of morphology and function, which not only provides empirical techniques for mitochondrial research on C. elegans, but also extends its framework to mammalian cell and organoid models, promoting the basic research and drug development targeting mitochondria.

Key words: Caenorhabditis elegans, Mitochondria, Oxidative respiration, Fiji data processing, Seahorse assay, Aging model

CLC Number:

Q95-33

SONG Mengjiao,SHEN Yidong. Approaches and Application Examples for Studying Mitochondrial Morphology and Function in Caenorhabditis elegans[J]. Laboratory Animal and Comparative Medicine, 2025, 45(6): 726-737. DOI: 10.12300/j.issn.1674-5817.2025.119.

Figures/Tables 8

References 31

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