ABSTRACT
Much under appreciated until recently, physiological mechanisms of cell death are required throughout the development and adulthood of all multicellular organisms [1,2]. From the formation of xylem in plants to the generation of the interdigital space in vertebrates, well-orchestrated cell death events are critical for the removal of superfluous cells as a vital part of tissue sculpting. Equally importantly, physiological cell death enables the elimination of unwanted extra cells to maintain cellular homeostasis in developed adults, as well as to rid the organisms of harmful cells or cells with serious cellular or genomic damage that are potentially dangerous. Morphologically recognized as apoptosis, physiological cell death is characterized by a distinct set of morphological and biochemical features, including chromatin condensation, internucleosomal DNA fragmentation, and, perhaps most importantly, cell surface alterations that signal for the rapid recognition and engulfment of apoptotic cells by neighboring phagocytic cells, thus avoiding the induction of inflammation [3].
