Control of the archaeal DNA damage-responsive pathway by phosphorylation of Orc1-2, the global regulator in Saccharolobus islandicus.

ABSTRACT: Archaea employ Orc1-2, an Orc1/Cdc6 family protein, to mediate DNA damage-responsive (DDR) regulation, which orchestrates a series of cellular responses to DNA damage. However, how the DDR process is regulated remains elusive. To investigate whether the Orc1-2 functions could be regulated by posttranslational modifications (PTMs), differential PTMs were analyzed for Orc1-2 proteins in cells of normal growth versus those in DNA damage-treated cells. We found only Orc1-2 proteins present in untreated cells are phosphorylated at T356. Since T356 is located in the DNA-binding pocket of the archaeal DDR regulator in the predicted structure, its phosphorylation may impair the DNA binding of the protein. Indeed, characterization of T356A, the phospho-ablative form, and T356D, the phospho-mimetic

SUBMITTER: Liu X 

PROVIDER: S-EPMC12490963 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature