Autophagy and cell death in Caenorhabditis elegans

Cell death is a major component of developmental programs. Controlled killing of specific cells at appropriate time points is required for normal growth and shaping of organisms. However, cellular demolition can also result in a variety of pathologies that are frequently fatal, when implemented inappropriately. Delineation of cell death mechanisms has been greatly facilitated by the use of simple model organisms such as the nematode worm Caenorhabditis elegans. Research in C. elegans has proven instrumental for the elucidation of the molecular mechanisms underlying both apoptotic and necrotic cell death. Here, we introduce the C. elegans model and review the current understanding of cell death pathways in this organism. We further focus on recent studies implicating autophagy, the main cellular process for bulk protein and organelle recycling, in nematode cell death. These studies reveal that autophagic mechanisms have a prominent role in both apoptosis and necrosis. We survey the relevant findings in C. elegans and also consider the contribution of autophagy in cell death in other experimental systems. Comparative analysis suggests that the involvement of autophagy in cell death is evolutionary conserved in metazoans. Thus, interfering with the autophagic process may facilitate therapeutic intervention in human pathologies where aberrant cell death is a contributing factor.