Linked Life Data

15218023

Source:http://linkedlifedata.com/resource/pubmed/id/15218023

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
35
pubmed:dateCreated
2004-8-23
pubmed:abstractText
The mechanism by which folate deficiency influences carcinogenesis is not well established, but a phenotype of DNA strand breaks, mutations, and chromosomal instability suggests an inability to repair DNA damage. To elucidate the mechanism by which folate deficiency influences carcinogenicity, we have analyzed the effect of folate deficiency on base excision repair (BER), the pathway responsible for repairing uracil in DNA. We observe an up-regulation in initiation of BER in liver of the folate-deficient mice, as evidenced by an increase in uracil DNA glycosylase protein (30%, p < 0.01) and activity (31%, p < 0.05). However, no up-regulation in either BER or its rate-determining enzyme, DNA polymerase beta (beta-pol) is observed in response to folate deficiency. Accordingly, an accumulation of repair intermediates in the form of DNA single strand breaks (37% increase, p < 0.03) is observed. These data indicate that folate deficiency alters the balance and coordination of BER by stimulating initiation without subsequently stimulating the completion of repair, resulting in a functional BER deficiency. In directly establishing that the inability to induce beta-pol and mount a BER response when folate is deficient is causative in the accumulation of toxic repair intermediates, beta-pol-haploinsufficient mice subjected to folate deficiency displayed additional increases in DNA single strand breaks (52% increase, p < 0.05) as well as accumulation in aldehydic DNA lesions (38% increase, p < 0.01). Since young beta-polhaploinsufficient mice do not spontaneously exhibit increased levels of these repair intermediates, these data demonstrate that folate deficiency and beta-pol haploinsufficiency interact to increase the accumulation of DNA damage. In addition to establishing a direct role for beta-pol in the phenotype expressed by folate deficiency, these data are also consistent with the concept that repair of uracil and abasic sites is more efficient than repair of oxidized bases.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
27
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
36504-13
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:15218023-Animal Feed, pubmed-meshheading:15218023-Animals, pubmed-meshheading:15218023-Blotting, Western, pubmed-meshheading:15218023-Cell Nucleus, pubmed-meshheading:15218023-DNA, pubmed-meshheading:15218023-DNA Damage, pubmed-meshheading:15218023-DNA Glycosylases, pubmed-meshheading:15218023-DNA Polymerase beta, pubmed-meshheading:15218023-DNA Repair, pubmed-meshheading:15218023-Dietary Supplements, pubmed-meshheading:15218023-Folic Acid, pubmed-meshheading:15218023-Folic Acid Deficiency, pubmed-meshheading:15218023-Heterozygote, pubmed-meshheading:15218023-Liver, pubmed-meshheading:15218023-Male, pubmed-meshheading:15218023-Mice, pubmed-meshheading:15218023-Mice, Inbred C57BL, pubmed-meshheading:15218023-Models, Chemical, pubmed-meshheading:15218023-Oxygen, pubmed-meshheading:15218023-Tumor Suppressor Protein p53, pubmed-meshheading:15218023-Up-Regulation, pubmed-meshheading:15218023-Uracil, pubmed-meshheading:15218023-Uracil-DNA Glycosidase
pubmed:year
2004
pubmed:articleTitle
Imbalanced base excision repair in response to folate deficiency is accelerated by polymerase beta haploinsufficiency.
pubmed:affiliation
Department of Nutrition and Food Science, Wayne State University, Detroit, MI 48202, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't