- Thymine dimer
A thymine dimer is the covalent bonding of two adjacent
thymine residues within aDNA molecule, often catalyzed by ultraviolet radiation or chemical mutagenic agents. It is an example of a more general type of DNA damage known aspyrimidine dimers , which, as the name suggests, can occur between any adjacent pair of pyrimidine bases (such as between 2 cytosines or a cytosine and a uracil).Excision repair enzyme s and theDNA repair system can often recognize and repair this type of damage by the large kink in the DNA that it causes. In many organisms (excluding placental mammals such as humans), DNAphotolyase s can repair the damage directly by cleaving the dimer.Unrepaired or mis-repaired thymine dimers and the resultant mutations can contribute to the development of
skin cancer s.ee also
*
Nucleotide excision repair
*Pyrimidine dimers (Cyclobutyl dimer)
*Tanning activator External links
* [http://antibodybeyond.com/reviews/antigen-t/thymine-dimer.htm Thymine dimer antibody review]
References
* Essen LO, Klar T. (2006). [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=Abstract&list_uids=16699813 Light-driven DNA repair by photolyases.] "Cell Mol Life Sci" 63 (11), 1266-77.
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