Uracil in DNA and its processing by different DNA glycosylases

Uracil in DNA may result from incorporation of dUMP during replication and from spontaneous or enzymatic deamination of cytosine, resulting in U:A pairs or U:G mismatches, respectively. Uracil generated by activation-induced cytosine deaminase (AID) in B cells is a normal intermediate in adaptive im...

Full description

Saved in:
Bibliographic Details
Published in:Philosophical transactions of the Royal Society of London. Series B. Biological sciences 2009-03, Vol.364 (1517), p.563-568
Main Authors: Visnes, Torkild, Doseth, Berit, Pettersen, Henrik Sahlin, Hagen, Lars, Sousa, Mirta M.L, Akbari, Mansour, Otterlei, Marit, Kavli, Bodil, Slupphaug, Geir, Krokan, Hans E
Format: Article
Language:English
Subjects:
AIDS
B cell lymphoma
B lymphocytes
Base Excision Repair
Cell cycle
Cell lines
Class Switch Recombination
Cytosine Deaminase - metabolism
Cytosine Deamination
DNA
DNA - chemistry
DNA damage
DNA Glycosylases - metabolism
DNA Mismatch Repair
DNA repair
Enzymes
Genetic mutation
Immunity, Active - genetics
Immunity, Active - immunology
Models, Immunological
Review
Somatic Hypermutation
Uracil - metabolism
Uracil-Dna Glycosylase
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Uracil in DNA may result from incorporation of dUMP during replication and from spontaneous or enzymatic deamination of cytosine, resulting in U:A pairs or U:G mismatches, respectively. Uracil generated by activation-induced cytosine deaminase (AID) in B cells is a normal intermediate in adaptive immunity. Five mammalian uracil-DNA glycosylases have been identified; these are mitochondrial UNG1 and nuclear UNG2, both encoded by the UNG gene, and the nuclear proteins SMUG1, TDG and MBD4. Nuclear UNG2 is apparently the sole contributor to the post-replicative repair of U:A lesions and to the removal of uracil from U:G contexts in immunoglobulin genes as part of somatic hypermutation and class-switch recombination processes in adaptive immunity. All uracil-DNA glycosylases apparently contribute to U:G repair in other cells, but they are likely to have different relative significance in proliferating and non-proliferating cells, and in different phases of the cell cycle. There are also some indications that there may be species differences in the function of the uracil-DNA glycosylases.
ISSN:0962-8436
1471-2970
DOI:10.1098/rstb.2008.0186