cell death

Different types of cell death have classically been identified by discrete morphological changes. The hallmarks of apoptosis include cell shrinkage, nuclear fragmentation and membrane blebbing whereas necroptosis is characterized by cell swelling and plasma membrane breakdown. While these two forms of cell death are clearly distinct, substantial crosstalk occurs between them.  Accordingly, it is becoming increasingly important to understand how these processes differ and to understand ways to differentiate them in cellular populations. 

Cell death via apoptosis is a basic cellular function occurring through the cell death receptor family and their ligands which signal through downstream adaptor molecules and the caspase protease family. Caspases have a precursor form composed of a prodomain, and large and small catalytic subunit, and are activated through a cleavage adjacent to an aspartate to liberate units and allow formation of an a2b2 tetramer. Caspase 3 is a cytoplasmic caspase with two isoforms (one acts as a dominant negative inhibitor), and is involved in the activation cascade for apoptosis execution.