Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2011-2-3
pubmed:abstractText
In the absence of core nonhomologous end-joining (NHEJ) factors, Ab gene class-switch recombination (CSR) uses an alternative end-joining (A-EJ) pathway to recombine switch (S) region DNA breaks. Previous reports showing decreased S-junction microhomologies in MSH2-deficient mice and an exonuclease 1 (EXO1) role in yeast microhomology-mediated end joining suggest that mismatch repair (MMR) proteins might influence A-EJ-mediated CSR. We have directly investigated whether MMR proteins collectively or differentially influence the A-EJ mechanism of CSR by analyzing CSR in mice deficient in both XRCC4 and individual MMR proteins. We find CSR is reduced and that Igh locus chromosome breaks are reduced in the MMR/XRCC4 double-deficient B cells compared with B cells deficient in XRCC4 alone, suggesting MMR proteins function upstream of double-strand break formation to influence CSR efficiency in these cells. Our results show that MLH1, EXO1, and MSH2 are all important for efficient A-EJ-mediated CSR, and we propose that MMR proteins convert DNA nicks and point mutations into dsDNA breaks for both C-NHEJ and A-EJ pathways of CSR. We also find Mlh1-XRCC4(-) B cells have an increased frequency of direct S junctions, suggesting that MLH1 proteins may have additional functions that influence A-EJ-mediated CSR.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Adaptor Proteins, Signal Transducing, http://linkedlifedata.com/resource/pubmed/chemical/DNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Deoxyribonucleases, Type II..., http://linkedlifedata.com/resource/pubmed/chemical/Exodeoxyribonucleases, http://linkedlifedata.com/resource/pubmed/chemical/Mlh1 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Msh2 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/MutS Homolog 2 Protein, http://linkedlifedata.com/resource/pubmed/chemical/Nuclear Proteins, http://linkedlifedata.com/resource/pubmed/chemical/XLF protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/XRCC4 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/endodeoxyribonuclease NheI, http://linkedlifedata.com/resource/pubmed/chemical/exodeoxyribonuclease I
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1550-6606
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
186
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2336-43
pubmed:dateRevised
2011-10-17
pubmed:meshHeading
pubmed-meshheading:21242524-Adaptor Proteins, Signal Transducing, pubmed-meshheading:21242524-Animals, pubmed-meshheading:21242524-B-Lymphocyte Subsets, pubmed-meshheading:21242524-Cells, Cultured, pubmed-meshheading:21242524-DNA Breaks, Double-Stranded, pubmed-meshheading:21242524-DNA Damage, pubmed-meshheading:21242524-DNA Repair, pubmed-meshheading:21242524-DNA-Binding Proteins, pubmed-meshheading:21242524-Deoxyribonucleases, Type II Site-Specific, pubmed-meshheading:21242524-Exodeoxyribonucleases, pubmed-meshheading:21242524-Immunoglobulin Class Switching, pubmed-meshheading:21242524-Mice, pubmed-meshheading:21242524-Mice, Knockout, pubmed-meshheading:21242524-Mice, Transgenic, pubmed-meshheading:21242524-MutS Homolog 2 Protein, pubmed-meshheading:21242524-Nuclear Proteins, pubmed-meshheading:21242524-Point Mutation
pubmed:year
2011
pubmed:articleTitle
Mismatch repair proteins MSH2, MLH1, and EXO1 are important for class-switch recombination events occurring in B cells that lack nonhomologous end joining.
pubmed:affiliation
Department of Pathology, Tufts University School of Medicine, Boston, MA 02111, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, N.I.H., Extramural