Mitophagy Dynamics in Caenorhabditis elegans
Mitochondrial selective autophagy (mitophagy) is a critical cellular process for mitochondrial homeostasis and survival both under basal and stress conditions. Distinct cell types display different requirements for mitochondrial turnover depending on their metabolic status, differentiation state, and environmental cues. This points to the necessity of developing novel tools for real-time, tissue-specific assessment of mitophagy. Caenorhabditis elegans is an invaluable model organism for this kind of analysis providing a platform for simultaneous monitoring of mitophagy in vivo in different tissues and cell types, during development, stress conditions, and/or throughout life span. In this chapter we describe three versatile, noninvasive methods, developed for monitoring in vivo early and late mitophagic events in body wall muscles and neuronal cells of C. elegans. These procedures can be readily used and/or provide insights into the generation of novel imaging methods to investigate further the role of mitophagy at the organismal level under normal and pathological conditions.
Key wordsAging Autophagosome Autophagy Caenorhabditis elegans DsRed Green fluorescent protein (GFP) Lysosomes Fluorescent microscopy Mitochondria Mitophagy mtRosella
We thank A. Pasparaki for expert technical support. We thank R. Devenish for providing the pAS1NB-CS-Rosella plasmid. Some nematode strains used in this work were provided by the Caenorhabditis Genetics Center, which is funded by the National Center for Research Resources (NCRR) of the National Institutes of Health (NIH). We thank A. Fire for plasmid vectors. This work was funded by grants from the European Research Council (ERC) and the European Commission 7th Framework Programme. K.P. is supported by an AXA Research Fund long-term fellowship. E.L. is supported by a Scholarship for Strengthening Post-Doctoral Research from The Greek State Scholarships Foundation (IKY) within the framework of the Operational Programme “Human Resources Development Program, Education and Life-Long Learning”.
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