title: Tissue regenerative delays and synthetic lethality in adult mice after combined deletion of Atr and Trp53.
abstract: Trp53 loss of function has previously been shown to rescue tissue maintenance and developmental defects resulting from DNA damage or DNA-repair gene mutations. Here, we report that p53 deficiency severely exacerbates tissue degeneration caused by mosaic deletion of the essential genome maintenance regulator Atr. Combined loss of Atr and p53 (Trp53(-/-)Atr(mKO)) led to severe defects in hair follicle regeneration, localized inflammation (Mac1(+)Gr1(+) infiltrates), accelerated deterioration of the intestinal epithelium and synthetic lethality in adult mice. Tissue degeneration in Trp53(-/-)Atr(mKO) mice was characterized by the accumulation of cells maintaining high levels of DNA damage. Moreover, the elevated frequency of these damaged cells in both progenitor and downstream compartments in Trp53(-/-)Atr(mKO) skin coincided with delayed compensatory tissue renewal from residual ATR-expressing cells. Together, our results indicate that the combined loss of Atr and Trp53 in adult mice leads to the accumulation of highly damaged cells, which, consequently, impose a barrier to regeneration from undamaged progenitors.
authors.affiliation: Abramson Family Cancer Research Institute, Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: Yaroslava
authors.initials: Y
authors.lastname: Ruzankina
authors.forename: David W
authors.initials: DW
authors.lastname: Schoppy
authors.forename: Amma
authors.initials: A
authors.lastname: Asare
authors.forename: Carolyn E
authors.initials: CE
authors.lastname: Clark
authors.forename: Robert H
authors.initials: RH
authors.lastname: Vonderheide
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Brown
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins / Q000378:metabolism; D016923:Cell Death; D018859:Hair Follicle / Q000166:cytology / Q000502:physiology*; D007413:Intestinal Mucosa / Q000166:cytology / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D017346:Protein Serine-Threonine Kinases / Q000172:deficiency* / Q000378:metabolism; D012038:Regeneration; D016159:Tumor Suppressor Protein p53 / Q000172:deficiency* / Q000378:metabolism
chemical_list: D018797:Cell Cycle Proteins; D016159:Tumor Suppressor Protein p53; C576897:Atr protein, mouse; D064007:Ataxia Telangiectasia Mutated Proteins; D017346:Protein Serine-Threonine Kinases