Biomaterial Database

SCE and DNA methylation. 1984

T Ikushima

The interrelationship between sister chromatid exchange (SCE) formation and DNA methylation was studied in Chinese hamster V79 and Indian muntjac cells. A DNA methylation inhibitor, 5-azacytidine (5AzaC), induced SCEs only when it had been present in cells for at least 2 rounds of DNA replication. This result suggests that SCEs are formed during replication of hemimethylated or demethylated DNA possessing 5AzaC, and that hypomethylated sites may become fully methylated after they pass 1 cell division. It also appears that hypomethylated DNA is not more sensitive to ultraviolet light (UV) or 3-aminobenzamide (3AMB) than normal chromosomes, but sensitized to mitomycin C (MMC) for the induction of SCEs. An analysis of sites of SCEs induced by 5AzaC within Indian muntjac chromosomes showed that the SCE frequency was enhanced at the 5 methylcytosine-rich regions where spontaneous SCEs were intensively suppressed. The SCE mechanism at the junction between contiguous replicons with different replication timing was discussed.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008745	Methylation	Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)	Methylations
D008937	Mitomycins	A group of methylazirinopyrroloindolediones obtained from certain Streptomyces strains. They are very toxic antibiotics used as ANTINEOPLASTIC AGENTS in some solid tumors. PORFIROMYCIN and MITOMYCIN are the most useful members of the group.
D008957	Models, Genetic	Theoretical representations that simulate the behavior or activity of genetic processes or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.	Genetic Models,Genetic Model,Model, Genetic
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D003412	Cricetulus	A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.	Hamsters, Armenian,Hamsters, Chinese,Hamsters, Grey,Armenian Hamster,Armenian Hamsters,Chinese Hamster,Chinese Hamsters,Grey Hamster,Grey Hamsters,Hamster, Armenian,Hamster, Chinese,Hamster, Grey
D003596	Cytosine	A pyrimidine base that is a fundamental unit of nucleic acids.
D003670	Deer	The family Cervidae of 17 genera and 45 species occurring nearly throughout North America, South America, and Eurasia, on most associated continental islands, and in northern Africa. Wild populations of deer have been established through introduction by people in Cuba, New Guinea, Australia, New Zealand, and other places where the family does not naturally occur. They are slim, long-legged and best characterized by the presence of antlers. Their habitat is forests, swamps, brush country, deserts, and arctic tundra. They are usually good swimmers; some migrate seasonally. (Walker's Mammals of the World, 5th ed, p1362)	Deers
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D004261	DNA Replication	The process by which a DNA molecule is duplicated.	Autonomous Replication,Replication, Autonomous,Autonomous Replications,DNA Replications,Replication, DNA,Replications, Autonomous,Replications, DNA