stress response pathway p53-dependent G1/S DNA damage checkpoint pathway transcription factor mediated signaling pathway p53 signaling pathway 2009-11-30T03:01:53Z KEGG:04115 PID:200206 PW:0000718 p53 transcription factor is a tumor suppressor frequently mutated in cancer. p53 is at the hub of many signaling and regulatory pathways. In response to various stresses, it promotes apoptosis, cell cycle arrest and other defense pathways via transcription dependent as well as independent routes. A key regulator of p53 is Mdm2. Mdm2 is a transcriptional target of p53 thus providing a negative feedback loop. pathway vpetri transcription pathway via transcription factor mediated signaling