Ouroboros on Aging Research in Yeast
Yeast has long been important in aging research: "The budding yeast Saccharomyces cerevisiae has been a valuable model system in biogerontology, dating back to the very earliest years of the modern synthesis of molecular genetics with the study of lifespan regulation. From yeast we first learned about the sirtuins, and it continues to teach us much about the mechanisms of lifespan extension by calorie restriction. ... An under-appreciated feature of yeast aging is that [a] yeast cell can die either by necrosis or by programmed cell death - i.e., apoptosis or something very much like it. That comes as a surprise to those of us who grew up thinking of apoptosis as a kind of 'noble sacrifice' made by a damaged cell in the context of a tissue or organ: damage leads to cancer, but not if it leads to cell death first; hence, there's a survival benefit to the organism if individual cells 'voluntarily' die in response to certain types of stress. But with no body to protect, why would a single-celled organism undergo apoptosis?"
Link: http://ouroboros.wordpress.com/2008/10/20/apoptosis-in-yeast/