Caspases: Activation, Regulation, and Function

The main effectors of apoptosis are proteases belonging to the caspase family. Caspases represent key mediators in the initiation and execution of the apoptotic program. The apoptotic caspases constitute a minimal two-step signaling pathway that culminates in the controlled demise of the affected cell. At the center of intense research for more than a decade and a half, a thorough picture of these regulatory proteases has emerged. A plethora of recent reports shed exciting new and refined light on their activation, regulation, and function. In addition to an advanced understanding of caspases in the apoptotic program, additional functions of these proteases in other pathways and their intriguing regulation by new signaling platforms have surfaced. With caspases affecting biological processes extending from apoptosis to other forms of cell death and inflammation, a closer look at these regulatory proteases is paramount for our understanding of cell signaling.