6-4 photolyase differentially modulates transcription in the vertebrate circadian clock.

ABSTRACT: The cryptochrome-photolyase family, a highly conserved set of flavoproteins, mediates many direct and indirect responses to sunlight. While the photolyases are light-dependent enzymes which catalyze photoreactivation repair of UV-induced DNA damage, the cryptochromes serve as circadian clock components and photoreceptors. Do DNA repair and circadian clock functions overlap in these flavoproteins? While 6-4 photolyase (6-4phr) is well-documented to repair UV-induced 6-4 photoproducts, we demonstrate that loss of 6-4phr function in fish cells and fin clips significantly attenuates circadian rhythms of period gene expression. Importantly, 6-4phr represses, as well as activates transcription directed by E-box and D-box enhancer elements respectively. Furthermore, we document physical interacti

SUBMITTER: Li H 

PROVIDER: S-EPMC12716789 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature