4.1.99.3 cyclobutadipyrimidine (in DNA) - 4.1.99.3 cyclobutadipyrimidine (in DNA) the enzyme is involved in biological photoreactivation 4.1.99.3 cyclobutadipyrimidine (in DNA) photolyases utilize near-ultraviolet blue light to specifically repair the major photoproducts of UV-induced damaged DNA. The enzyme specifically repairs CPD lesions 4.1.99.3 cyclobutadipyrimidine (in DNA) the enzyme catalyses light-driven DNA repair and photoreduction, but in contrast to class I enzymes lacks a high degree of binding discrimination between UV-damaged and intact duplex DNA 4.1.99.3 cyclobutadipyrimidine in DNA DNA repair enzyme can absorb blue/ultraviolet A light as energy and split a pyrimidine dimer induced by ultraviolet radiation. PHR1 gene encodes a functional photolyase. The PHR1 transcripts are specifically enhanced by near-ultraviolet radiation (300-400 nm) and by sunlight 4.1.99.3 cyclobutadipyrimidine in DNA the enzyme is one of the main factors determining UVB sensitivity in Oryza sativa. Cultivar Sasanishiki is resistant to the damaging effects of UVB while cultivar Norin 1 is less resistant. Amino acid position 126 is Arg in cultivar Norin 1 and Gln in cultivar Sasanishiki. The single amino acid alteration from Gln to Arg leads to a deficit of CPD photolyase activity 4.1.99.3 cyclobutadipyrimidine in DNA - 4.1.99.3 cyclobutadipyrimidine in DNA DNA repair activity 4.1.99.3 cyclobutadipyrimidine in DNA the enzyme binds to DNA containing pyrimidine dimers with high affinity and then breaks the cyclobutane ring joining the two pyrimidines of the dimer in a light-dependent reaction, 300-500 nm 4.1.99.3 cyclobutadipyrimidine in DNA light-dependent(300-600 nm) monomerization of cyclobutyl pyrimidine dimers, formed between adjacent pyrimidines on the same DNA strand, upon exposure to UV irradiation, 220-320 nm 4.1.99.3 cyclobutadipyrimidine in DNA the enzyme converts the energy of light of near UV to visible wavelengths into chemical energy to break the cyclobutane ring of pyrimidine dimers in DNA and thus prevents the lethal and mutagenic effects of far UV, 200-300 nm 4.1.99.3 additional information enzyme promotes virus survival in the environment 4.1.99.3 additional information expression in transgenic mice leads to superior survival, reduced acute UV effects like erythema, hyperplasia or apoptosis when treated with photoreactivating light 4.1.99.3 additional information light-dependent repair of UV-induced damage products in DNA by direct reversal of base damage rather than via excision repair pathways 4.1.99.3 additional information major pathway to remove UV-induced DNA lesions from the genome 4.1.99.3 additional information photolyase repairs nucleosome-free DNA rapidly, while repair of nucleosomes is inhibited severely 4.1.99.3 additional information predominant role of photolyase is CDP repair of an origin or replication 4.1.99.3 additional information environmental stress enzyme 4.1.99.3 additional information photoreduction by intraprotein electron transfer is not part of the photolyase photocycle under physiological conditions 4.1.99.3 additional information absolute dependence of catalysis by photolyase on light 4.1.99.3 additional information CPD photolyase, which rapidly repairs CPDs, is essential for plant survival under sunlight containing UVB 4.1.99.3 additional information CPDs and 6-4PPs play different roles in UV-induced cell death in normal and NER-deficient human cells 4.1.99.3 additional information CryA can repair DNA upon exposure to UVA light similar to other photolyase proteins, CryA represses sexual development under UVA350-370 nm light and exhibits a regulatory function during light-dependent development and DNA repair activity, in the wild type strain mechanisms such as excision repair mask the DNA photolyase activity of CryA 4.1.99.3 additional information pre-inoculation UV-C (254 nm) treatment of normally susceptible Arabidopsis thaliana accessions induces prolonged, dose-dependent resistance to virulent isolates of the phytopathogenic oomycete Hyaloperonospora parasitica with cyclobutane pyrimidine dimers and (6-4) photoproducts playing a key role in this response 4.1.99.3 additional information the native rice CPD photolyase is phosphorylated, whereas the Escherichia coli-expressed rice CPD photolyase is not 4.1.99.3 additional information PHR1 and PHR2 are able to bind the CLOCK protein, a transcription activator controlling the molecular circadian clock. But only for PHR2, the physical interaction with CLOCK represses CLOCK/BMAL1-driven transcription, binding of photolyase per se is not sufficient to inhibit the CLOCK/BMAL1 heterodimer 4.1.99.3 additional information PhrB does not function as a photolyase 4.1.99.3 additional information the enzyme has blue light photoreceptor activity and CPD photolyase activity. Signaling might be mediated by the PHR besides its effects on the C-terminal extension, conformational changes in cryptochromes upon illumination, overview