How Do Toxic Agents Affect Cell Cycle Checkpoints?
Toxic agents can disrupt cell cycle checkpoints by interfering with the proteins and signaling pathways that govern these processes. For instance, DNA-damaging agents like radiation and certain chemicals can activate the DNA damage response, halting cell cycle progression to facilitate repair. If the damage is irreparable, cells may undergo apoptosis to prevent the propagation of errors. Some toxicants may also mimic or block the action of key regulatory proteins, such as p53 and cyclin-dependent kinases (CDKs), leading to checkpoint failure and uncontrolled cell proliferation.
