A set of genes (growth arrest- and DNA damage-inducible genes) that are activated when DNA is damaged. Gadd-34 (protein phosphatase 1 regulatory subunit 15A, PPP1R15A, 674 aa) mediates growth arrest and apoptosis following DNA damage or negative growth signals. Gadd-45 (165 aa) is strongly induced by X-rays. There are actually three related proteins, gadd-45 α, β, and γ, all induced by stress. Gadd-45α associates with the cyclin dependent kinase inhibitor p21Cip1 and proliferating cell nuclear antigen, stimulates DNA excision repair in vitro and inhibits entry of cells into S phase. Gadd-153 (C/EBP-homologous protein, CHOP, 169 aa) is not induced by X-rays but by alkylating agents and ultraviolet light and acts as an inhibitor of the transcription factors C/EBP and LAP. It also seems to activate Gadd-34. The Gadd-153 gene is consistently rearranged in myxoid liposarcomas.
Subjects: Medicine and Health.