Fig. 1

Molecular mechanism of apoptosis and necroptosis. Death receptor mediates both extrinsic apoptosis as well as necroptosis; RIPK1 plays a key role in apoptosis and necroptosis. Activation of caspase-8 drives the pathway towards apoptosis while its inhibition leading to necroptosis. During necroptosis, RIPK1 and RIPK3 interact with each other resulting in the formation of functional heterodimer complex; this complex promotes oligomerization of MLKL by phosphorylating it. Oligomeric form of MLKL translocates towards the plasma membrane from cytosol resulting in the formation of the pore, causing an inflammatory response. In spite of pore formation, MLKL also mediates its effect after interacting with ion channels