Pyrimidine dimers are the primary cause of melanomas in humans. A cyclobutane pyrimidine dimer (CPD) contains a four membered ... A 6-4 photoproduct (6-4 pyrimidine-pyrimidone or 6-4 pyrimidine-pyrimidinone) is an alternate dimer consisting of a single ... The number of pyrimidine dimers induced per haploid genome at this dose was measured as 27,000. A mutant yeast strain defective ... It is a base excision repair enzyme specific for pyrimidine dimers. It is then able to cut open the AP site. Another type of ...

... (EC 3.1.25.1, endodeoxyribonuclease (pyrimidine dimer), bacteriophage T4 ... Deoxyribonuclease+(pyrimidine+dimer) at the U.S. National Library of Medicine Medical Subject Headings (MeSH) Portal: Biology v ... Mechanism of action of two endonucleases specific for DNA containing pyrimidine dimers". The Journal of Biological Chemistry. ... This enzyme catalyses the following chemical reaction: Endonucleolytic cleavage near pyrimidine dimers to products with 5'- ...

Dimerization consists of the bonding of two monomers to form an oligomer, such as the formation of pyrimidine dimers as a ... Setlow, R. B. (1966). "Cyclobutane-type pyrimidine dimers in polynucleotides". Science. 153 (734): 379-386. Bibcode:1966Sci... ... In human skin cells, thousands of dimers may be formed in a day due to normal exposure to sunlight. DNA polymerase η may help ...

C double bonds of pyrimidines. Thymine dimers (T-T dimers) formed in between two thymines are the most abundant of the CPDs. ... "Cyclobutane-Type Pyrimidine Dimers in Polynucleotides". Science. 153 (3734): 379-386. Bibcode:1966Sci...153..379S. doi:10.1126/ ... Some related fenestranes are also found in nature.[citation needed] Cyclobutane photo dimers (CPD) are formed by photochemical ...

CYCLOBUTANE- TYPE PYRIMIDINE DIMERS IN POLYNUCLEOTIDES, R. B. Setlow, Science 1966 Vol. 153, p. 379, DOI: 10.1126/science. ... DNA: photodimerization leading to cyclobutane pyrimidine dimers. Examples of photochemical organic reactions are electrocyclic ... Such dimers interfere with transcription. The beneficial effects of sunlight are associated with the photochemically induced ... The dimerization of alkenes is relevant to the photodamage of DNA, where thymine dimers are observed upon illuminating DNA to ...

thymine dimer See pyrimidine dimer. tissue tissue-specific gene expression Gene function and expression which is restricted to ... pyrimidine dimer A type of molecular lesion caused by photochemical damage to DNA or RNA, whereby exposure to ultraviolet (UV) ... Pyrimidine dimers are usually quickly corrected by nucleotide excision repair, but uncorrected lesions can inhibit or arrest ... or a pyrimidine nucleotide is substituted for another pyrimidine (C ↔ T). Contrast transversion. translation The second step in ...

Its DNA damage effect produces cyclobutane-type pyrimidine dimers. Besides the direct effects, UV-C also induces resistance ...

The absorbed energy can result in defects including pyrimidine dimers. These dimers can prevent replication or can prevent the ... Recently, it has been shown that these dimers are fluorescent. Mercury-based lamps operating at low vapor pressure emit UV ... This understanding was solidified by the 1960s through research demonstrating the ability of UV-C to form thymine dimers, ...

They mainly convert pyrimidine dimers into a normal pair of pyrimidine bases. Photolyases bind complementary DNA strands and ... Teranishi, M., Nakamura, K., Morioka, H.,Yamamoto, K. and Hidema, J. (2008). "The native cyclobutane pyrimidine dimer ... is activated by light energy and acts as an electron donor to break the pyrimidine dimer. On the basis of sequence similarities ... and deoxyribonucleate pyrimidine dimer lyase (photosensitive). This enzyme belongs to the family of lyases, specifically in the ...

"Cleavage of Pyrimidine Dimers in Specific DNA Sequences by a Pyrimidine Dimer DNA-Glycosylase of M.luteus". Nature. 285 (5767 ... coli DNA Photolyase Reverses Cyclobutane Pyrimidine Dimers but not Pyrimidine-Pyrimidone (6-4) Photoproducts". Journal of ... Gordon, LK; Haseltine WA (1980). "Comparison of the Cleavage of Pyrimidine Dimers by the Bacteriophage T4 and M. luteus UV- ... Gordon, LK; Haseltine WA (1981). "Early Steps of Excision Repair of Cyclobutane Pyrimidine Dimers by the Micrococcus Luteus ...

UV-induced formation of pyrimidine dimers in DNA can lead to cell death unless the lesions are repaired. Most repair of these ... Douki T, von Koschembahr A, Cadet J (2017). "Insight in DNA Repair of UV-induced Pyrimidine Dimers by Chromatographic Methods ...

Cannistraro VJ, Pondugula S, Song Q, Taylor JS (2015). "Rapid deamination of cyclobutane pyrimidine dimer photoproducts at TCG ... the photoproduct is typically the cyclobutane pyrimidine dimer (CPD). Specificity for C>T appears to be due to the million-fold ... "The major mechanism of melanoma mutations is based on deamination of cytosine in pyrimidine dimers as determined by circle ... Signature 7 has a predominance of C>T substitutions at sites of adjacent pyrimidines (adjacent C or T), with a particularly ...

The tanning activator coumarin is known to induce thymine dimers (cyclobutane pyrimidine dimers). Other Web sites state ... Several substances are known to increase the amount of direct DNA damage (thymine dimers). In order to produce this action they ...

With UVB, the damage to DNA becomes direct, with photochemical formation of pyrimidine dimers. Narayanan, DL; Saladi, RN; Fox, ...

Many photodimers are now recognized, e.g. pyrimidine dimer, thiophosgene, diamantane. Another example was uncovered by Egbert ...

The pigment melanin in the fish epidermis partially protected against the induction of pyrimidine dimers. "Xiphophorus". ... pyrimidine dimers) by ultraviolet radiation, and the repair of such damage by photoreversal was demonstrated in the skin of ...

The neighboring pyrimidines form a cyclobutane pyrimidine dimer in a CPD lesion. DNA absorption of UV radiation can also lead ...

Such damages include bulky chemical adducts, UV-induced pyrimidine dimers, and several forms of oxidative damage. Mutations in ...

Cytosine methylations change the amount of UV light absorption of the nucleotide base, creating pyrimidine dimers. When ...

Such damages include bulky chemical adducts, ultraviolet-induced pyrimidine dimers, and several forms of oxidative damage. ...

Fitch ME, Nakajima S, Yasui A, Ford JM (November 2003). "In vivo recruitment of XPC to UV-induced cyclobutane pyrimidine dimers ... the cyclobutane pyrimidine dimer), and binds weakly to DNA that has no DNA damage. The DDB2 component of the heterodimer ... protein complex recognizes a cyclobutane pyrimidine dimer, mismatches, apurinic/apyrimidinic sites, and compound lesions in DNA ... repair pathway to enter the chromatin and repair the DNA damaged by the UV-induced presence of cyclobutane pyrimidine dimers. ...

Protić-Sabljić M, Kraemer KH (October 1985). "One pyrimidine dimer inactivates expression of a transfected gene in xeroderma ...

The formation of pyrimidine dimers upon irradiation with UV light results in an abnormal covalent bond between adjacent ... Some examples are: UV-B light causes crosslinking between adjacent cytosine and thymine bases creating pyrimidine dimers. This ... proteins in the nucleotide excision repair pathway to enter the chromatin and repair UV-induced cyclobutane pyrimidine dimer ... RecA-ssDNA filaments activate LexA autoprotease activity, which ultimately leads to cleavage of LexA dimer and subsequent LexA ...

... pyrimidine dimer DNA-glycosylase, endonuclease V, deoxyribonucleate pyrimidine dimer glycosidase, pyrimidine dimer DNA ... "Cleavage of pyrimidine dimers in specific DNA sequences by a pyrimidine dimer DNA-glycosylase of M. luteus". Nature. 285 (5767 ... This enzyme catalyses the following chemical reaction Cleaves the N-glycosidic bond between the 5'-pyrimidine residue in ...

A major mechanism of NB-UVB is the induction of DNA damage in the form of pyrimidine dimers. This type of phototherapy is ... useful in the treatment of psoriasis because the formation of these dimers interferes with the cell cycle and stops it. The ...

Defective postreplication repair of cyclobutane pyrimidine dimers can lead to mutations that are the primary driver of melanoma ... cells are commonly defective in postreplication repair of DNA damages that are in the form of cyclobutane pyrimidine dimers, a ...

... pyrimidine-pyrimidone photoproducts and cyclobutane pyrimidine dimers. The helical domain at the n-terminus of DDB2 binds to UV ... Binding with high affinity to a helical domain of DDB2 in the dimer form, UV-DDB, is facilitated by the n-terminal alpha ...

... the formation of cyclobutane pyrimidine dimers and photoproducts formed between adjacent pyrimidine bases. These mutations may ...

This disease can cause light-skin, extreme freckling and facial lesions, as well as preventing the repair of pyrimidine dimers ... Such damage may include thymine dimers created by UV rays as well as the bulky distortions in DNA caused by oxidized ...

Ultraviolet (UV) light induces the formation of DNA damages including pyrimidine dimers (such as thymine dimers) and 6,4 ... "The Saccharomyces cerevisiae RAD9 cell cycle checkpoint gene is required for optimal repair of UV-induced pyrimidine dimers in ... After being incubated to permit DNA repair, the extent of pyrimidine dimerization (which is indicative of DNA damage) was ...