The Polymerase Activity of Mammalian DNA Pol ζ Is Specifically Required for Cell and Embryonic Viability

• DOI: 10.1371/journal.pgen.1005759
• Publication Date: 2016-01-04T18:42:50Z
• Authors: Sabine S. Lange; Junya Tomida; Karen S. Boulware; Sarita Bhetawal; Richard D. Wood
• Keywords: DNA clamp

DNA polymerase ζ (pol ζ) is exceptionally important for maintaining genome stability. Inactivation of the Rev3l gene encoding catalytic subunit causes a high frequency chromosomal breaks, followed by lethality in mouse embryos and primary cells. Yet it not known whether activity pol specifically essential, as large REV3L protein also serves multiprotein scaffold translesion synthesis via multiple conserved structural domains. We report that cDNA rescues genomic instability damage sensitivity Rev3l-null immortalized fibroblast cell lines. A harboring mutations aspartate residues domain could rescue these phenotypes. To investigate role vivo, knock-in was constructed with this polymerase-inactivating alteration. No homozygous mutant mice were produced, occurring during embryogenesis. Primary fibroblasts from showed growth defects, elevated double-strand breaks cisplatin similar to fibroblasts. tested severe Rev3l-/- phenotypes be rescued deletion η, has been reported chicken DT40 However, Polh-/- inviable, derived sensitive Polh+/+ Therefore, functions viability, embryonic viability stability are directly dependent on its activity, cannot ameliorated an additional η. These results validate encourage approach targeting sensitize tumors damaging agents.