The growth arrest and DNA damage GADD45 proteins, which include GADD45A, GADD45B , and GADD45G, are implicated as stress sensors that modulate the response of mammalian cells to genotoxic/physiological stress, and modulate tumor formation [, , ]. GADD45 proteins interact with a number of other proteins implicated in stress responses, including PCNA, p21, Cdc2/CyclinB1, MEKK4, and p38 kinase. GADD45 stimulates DNA excision repair in vitro and inhibits the entry of cells into S phase during the cell cycle.
