WebAug 30, 2014 · Exposure to the ultraviolet component of sunlight causes DNA damage, which subsequently leads to mutations, cellular transformation, and cell death. DNA photoproducts with (6-4) pyrimidine-pyrimidone adducts are more mutagenic than cyclobutane pyrimidine dimers. These lesions must be repaired because of the high … WebSelect search scope, currently: articles+ all catalog, articles, website, & more in one search; catalog books, media & more in the Stanford Libraries' collections; articles+ journal articles & other e-resources

Requirement of transcription-coupled nucleotide excision repair …

WebPhotochemical cyclobutane dimerization of adjacent thymines generates the major lesion in DNA caused by exposure to sunlight. Not all nucleotide sequences and structures are equally susceptible to this reaction or its potential to create mutations. A cyclobutane pyrimidine dimer (CPD) contains a four membered ring arising from the coupling of the two double-bonded carbons of each of the pyrimidines. Such dimers interfere with base pairing during DNA replication, leading to mutations. A 6–4 photoproduct (6–4 pyrimidine–pyrimidone or 6–4 … See more Pyrimidine dimers are molecular lesions formed from thymine or cytosine bases in DNA via photochemical reactions, commonly associated with direct DNA damage. Ultraviolet light (UV; particularly UVB) … See more Due to the excellent photochemical properties of DNA, this nature-made molecule is damaged by only a tiny fraction of the … See more Pyrimidine dimers introduce local conformational changes in the DNA structure, which allow recognition of the lesion by repair enzymes. In most organisms (excluding placental mammals such as humans) they can be repaired by photoreactivation. … See more • DNA repair See more Translesion polymerases frequently introduce mutations at pyrimidine dimers, both in prokaryotes (SOS mutagenesis) and in eukaryotes. … See more A study by Hanson suggests sunscreen that penetrates into the skin and thereby amplifies the amount of free radicals and oxidative stress contributes to the formation of melanoma, but this idea has not been validated by other researchers. See more Direct DNA damage is reduced by sunscreen. This prevents sunburn. When the sunscreen is at the surface of the skin, it filters the UV rays, which attenuates the intensity. Even … See more know lyrics system of a down

Dynamics and mechanism of cyclobutane pyrimidine …

WebAug 4, 2009 · The stereochemistry of the thymine photodimers was assigned by comparing the base portion of the photoproducts with authentic thymine cyclobutane dimers ( 17, 30, 31) ( Fig. S2 B ). The base portion of the photodimers was obtained by treating the trinucleotides and tetranucleotides with 70% hydrogen fluoride in pyridine (HF/pyridine) ( … WebInstead, repair of classical NER substrates, cyclobutane pyrimidine dimer and N-(deoxyguanosin-8-yl)-2-acetylaminofluorene, occurred even when TC-NER was disrupted. The strict requirement of TC-NER highlights cyclo-dA and cyclo-dG as candidate damage types, accountable for cytotoxic and degenerative responses in individuals affected by … WebMay 23, 2011 · CPD photolyase uses light to repair cyclobutane pyrimidine dimers (CPDs) formed between adjacent pyrimidines in UV-irradiated DNA. The enzyme harbors an … redalyc chile