Figure 31.

Pathways that follow DNA damage may result in PCD or cell survival through autophagy, or checkpoint deficiency. (A) DNA damage inhibits TOR signaling, which promotes the formation of an ATG protein complex, thereby bringing about autophagy. Autophagy may contribute to cell survival as well as to cell death by PCD. (B) DNA damage may cause mutations in genes encoding checkpoint RAD proteins and/or proteins involved in DNA replication initiation, as well as the simultaneous deletion of genes encoding checkpoint kinases. Such protein defects lead to deficient checkpoints, thereby causing cells to enter M-phase prematurely with damaged DNA or incompletely replicated DNA, resulting in ROS generation, mitotic catastrophe, and subsequently PCD. This figure was previously published in ref. [1247]