First Author | Larsen E | Year | 2003 |
Journal | Mol Cell Biol | Volume | 23 |
Issue | 15 | Pages | 5346-53 |
PubMed ID | 12861020 | Mgi Jnum | J:84556 |
Mgi Id | MGI:2668283 | Doi | 10.1128/MCB.23.15.5346-5353.2003 |
Citation | Larsen E, et al. (2003) Proliferation failure and gamma radiation sensitivity of Fen1 null mutant mice at the blastocyst stage. Mol Cell Biol 23(15):5346-53 |
abstractText | Flap endonuclease 1 (FEN1) has been shown to remove 5' overhanging flap intermediates during base excision repair and to process the 5' ends of Okazaki fragments during lagging-strand DNA replication in vitro. To assess the in vivo role of the mammalian enzyme in repair and replication, we used a gene-targeting approach to generate mice lacking a functional Fen1 gene. Heterozygote animals appear normal, whereas complete depletion of FEN1 causes early embryonic lethality. Fen1(-/-) blastocysts fail to form inner cell mass during cellular outgrowth, and a complete inactivation of DNA synthesis in giant cells of blastocyst outgrowth was observed. Exposure of Fen1(-/-) blastocysts to gamma radiation caused extensive apoptosis, implying an essential role for FEN1 in the repair of radiation-induced DNA damage in vivo. Our data thus provide in vivo evidence for an essential function of FEN1 in DNA repair, as well as in DNA replication. |