Studies in S. cerevisiae have identified conserved longevity pathways, and may be important in elucidating how CR may differentially effect specific tissues through the CLS model, which mirrors the aging process of post-mitotic cells such as neurons and muscle cells, and the RLS model, which mirrors the aging of dividing cells in higher eukaryotes such as fibroblasts, lymphocytes, and stem cells. In this figure, the specific, as well as shared, interventions that lead to longevity extension in these two pathways are outlined. Interventions that affect yeast longevity in the CLS model are further divided by the phase of CLS in which they must be present to have beneficial effect.