An automated phenotype-based microscopy screen to identify pro-longevity interventions acting through mitochondria in C. elegans.

Mitochondria are multifunctional organelles that play a central role in cellular homeostasis. Severe mitochondrial dysfunction leads to life-threatening diseases in humans and accelerates the aging process. Surprisingly, moderate reduction of mitochondrial function in different species has anti-aging effects. High-throughput screenings in the nematode Caenorhabditis elegans lead to the identification of several pro-longevity genetic and pharmacological interventions. Large-scale screens, however, are manual, subjective, time consuming and costly. These limitations could be reduced by the identification of automatically quantifiable biomarkers of healthy aging. In this study we exploit the distinct and reproducible phenotypes described in C. elegans upon different levels of mitochondrial alteration to develop an automated high-content strategy to identify new potential pro-longevity interventions. Utilizing the microscopy platform Cellomics ArrayScan Reader, we optimize a workflow to automatically and reliably quantify the discrete phenotypic readouts associated with different degrees of silencing of mitochondrial respiratory chain regulatory proteins, and validate the approach with mitochondrial-targeting drugs known to extend lifespan in C. elegans. Finally, we report that a new mitochondrial ATPase modulator matches our screening phenotypic criteria and extends nematode's lifespan thus providing the proof of principle that our strategy could be exploited to identify novel mitochondrial-targeted drugs with pro-longevity activity. This article is part of a Special Issue entitled: Mitochondrial Dysfunction in Aging.