the major 3' DNA exonuclease in mammalian cells. Normally associates with the endoplasmic reticulum (ER). Translocates to the nucleus at S phase after DNA damage by gamma-irradiation or hydroxyurea. Trex1-deficient cells show defective G1/S transition, with single-stranded DNA molecules persisting after S phase and accumulating in the ER. Degrades ssDNA. Prevents chronic checkpoint activation and inappropriate immune activation. Mutations cause Aicardi-Goutieres syndrome, an autoimmune disorder. Trex1a(-/-) mice have autoinflammatory responses. The gene for this protein is either identical to or adjacent to that of ATRIP. Some of the mRNAs that encode TREX1 also encode ATRIP in another reading frame. Three alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: Cell cycle regulation; DNA repair, damage; DNA-binding; Deoxyribonuclease; EC 18.104.22.168