Which enzyme class is responsible for cleaving specific proteins during apoptosis?

The enzyme class responsible for cleaving specific proteins during apoptosis is proteases. In the context of apoptosis, proteases known as caspases play a central role. They are a subgroup of cysteine proteases that are activated in the apoptotic pathway and are essential for the execution of programmed cell death. Caspases cleave various cellular substrates, leading to the morphological and biochemical changes associated with apoptosis, such as DNA fragmentation, cell shrinkage, and membrane blebbing. This specific cleavage action helps dismantle the cell in a controlled manner, ensuring that cellular components are managed appropriately and preventing unwanted inflammation.

Kinases, ligases, and phosphatases serve different functions in cellular processes. Kinases typically add phosphate groups to proteins, which can alter their activity or signaling pathways, but they do not cleave proteins. Ligases are involved in the joining of two large molecules by forming a new chemical bond, while phosphatases remove phosphate groups but also do not possess proteolytic activity. Thus, these other enzyme classes do not have the capacity to cleave proteins during apoptosis, confirming the significance of proteases in this cellular process.