First Author | Esposito G | Year | 2000 |
Journal | Proc Natl Acad Sci U S A | Volume | 97 |
Issue | 3 | Pages | 1166-71 |
PubMed ID | 10655502 | Mgi Jnum | J:60185 |
Mgi Id | MGI:1352950 | Doi | 10.1073/pnas.97.3.1166 |
Citation | Esposito G, et al. (2000) Mice reconstituted with DNA polymerase beta-deficient fetal liver cells are able to mount a T cell-dependent immune response and mutate their Ig genes normally. Proc Natl Acad Sci U S A 97(3):1166-71 |
abstractText | The ubiquitously expressed, error-prone DNA polymerase beta (polbeta) plays a role in base excision repair, and the involvement of this molecule in the nonhomologous end joining (NHEJ) process of DNA repair has recently been demonstrated in yeast. Polbeta-deficient mice are not viable, and studies on conditional mutants revealed a competitive disadvantage of polbeta(-/-) vs. wild-type cells. We show here that polbeta-deficient mice survive up to day 18.5 postcoitum, but die perinatally; a circumstance that allowed the investigation of a potential role of polbeta in lymphocyte development by transfer of fetal liver cells (FLC) derived from polbeta(-/-) embryos into lethally irradiated hosts. FLC transfers using mutant cells lead to an almost normal reconstitution of the lymphocyte compartment, indicating that polbeta-deficiency does not prevent V(D)J recombination, which is known to employ factors of the NHEJ pathway. Mice reconstituted with polbeta(-/-) FLC mount a normal T cell-dependent immune response against the hapten (4-hydroxy-3-nitrophenyl) acetyl (NP). Moreover, germinal center B cells from NP-immunized reconstituted mice show normal levels and patterns of somatic point mutations in their rearranged antibody genes, demonstrating that polbeta is not critically involved in somatic hypermutation. |