Comparative genomic hybridization of mouse liver and tumors from Acd mutant and wild type strains in p53 deficient background
Ontology highlight
ABSTRACT: DNA from tumors of 10 male mice were competitively hybridized with DNA from liver samples from the same mouse on NimbleGen CGH arrays to assess copy number changes in the tumors. Four of the mice were wildtype for Acd (ortholog of human TPP1), 2 of which were p53-/- and 2 of which were p53-/+. The other 6 mice were homozygous for the mutant acd allele of Acd. 3 of these mice were p53-/- and the other 3 were p53-/+. Mice were crosses from double heterozygote parental mice. These parental mice were crosses of heterozygous Acd mutant mice (in a mixed DW/JxCAST/Ei background) with heterozygous null p53 mice (C57BL6/J; Trp53-tm1Tyj).
Project description:Canola plants inoculated with plant growth-promoting bacteria either expressing ACC deaminase or not to determine the effect on plant gene expression using an Arabidopsis microarray. 3 replicates for each ACD+ and ACD- bacteria, each compared with untreated control.
Project description:Nude mice were allografted with medulloblastoma tumors derived from Ptch+/-p53-/- transgenic mouse and treated with vehicle or NVP-LDE225. RNA was prepared from tumours from vehicle or NVP-LDE225 treated nude mice allografted with medulloblastoma tumors derived from Ptch+/-p53-/- transgenic mouse and hybridized on the Affymetrix Mouse Genome 430A 2.0 RNA expression microarray.
Project description:To elucidate the effect of senescence in mouse colorectal tumor, the transcriptome of enterocytes from CKI alpha deletion mutants (CKI alpha KO), CKI alpha/p53 double deletion mutants (CKI alpha/p53 DKO) and CKI alpha heterozygous mice (CKI alpha Het) were determined by RNAseq.
Project description:This SuperSeries is composed of the following subset Series: GSE22005: Medulloblastoma tumors derived from Ptch+/-HIC+/- transgenic mouse allografted in nude mice GSE22006: Medulloblastoma tumors derived from Ptch+/-p53-/- transgenic mouse allografted in nude mice Refer to individual Series
Project description:In mouse, the adrenocortical dysplasia (acd) phenotype shows limb and body axis anomalies, as a result of p53-dependent apoptosis, and perinatal lethality. The p53 deficiency partially rescues anomalies, but not perinatal lethality, implicating the involvement of p53-independent mechanisms in the acd phenotype. Differentially expressed genes in acd mutant and double mutant embryos were identified. p53-dependent and –independent pathways contributing to acd phenotype were characterized. We used microarrays to analyze gene expression profiles of acd and double mutant embryos and to identify p53 dependent and –independent mechanisms underlying acd phenotype.
Project description:Wild type and mutant p53 were transfected in H1299 cells and the associated complexes were affinity purified. The p53 interacting proteins then analyzed by ms/ms.
Project description:Exercise is a fundamental component of human health that is associated with greater life expectancy and reduced risk of chronic diseases. While the beneficial effects of endurance exercise on human health are well established, the molecular mechanisms responsible for these observations remain unclear. Endurance exercise reduces the accumulation of mitochondrial DNA (mtDNA) mutations, alleviates multisystem pathology, and increases the lifespan of the mtDNA mutator mouse model of aging, in which the proof-reading capacity of mitochondrial polymerase gamma (POLG1) is deficient. Clearly, exercise recruited a POLG1-independent mtDNA repair pathway to induce these adaptations, a novel finding as POLG1 is canonically considered to be the sole mtDNA repair enzyme. Here we investigate the identity of this pathway, and show that endurance exercise prevents mitochondrial oxidative damage, attenuates telomere erosion, and mitigates cellular senescence and apoptosis in mtDNA mutator mice. Unexpectedly, we observe translocation of tumour suppressor protein p53 to mitochondria in response to endurance exercise that facilitates mtDNA mutation repair. Indeed, endurance exercise failed to prevent mtDNA mutations, induce mitochondrial biogenesis, preserve mitochondrial morphology, reverse sarcopenia, and mitigate premature mortality in mtDNA mutator mice with muscle-specific deletion of p53. Our data establish an exciting new role for p53 in exercise-mediated maintenance of the mtDNA genome, and presents mitochondrially-targeted p53 as a novel therapeutic modality for aging-associated diseases of mitochondrial etiology. Microarray analysis of gene expression from skeletal muscle (quadriceps femoris) from Mus musculus. N=23 samples per treatment were analysed for whole transcriptiome gene expression profile using NimbleGen Arrays. The treatment groups included wild-type C57Bl/6J mice as the control group, then two treatment groups which both contained homozygous knock-in mtDNA mutator mice (PolG; PolgAD257A/D257A). Once group of these heterozygous knock out mice received regular endurance exercise sessions while the other group remained sedentraty for 6 months. The control group specimens were wild-type litter mates to the transgenic knockout mice.
Project description:The tumor suppressor protein p53 is a transcription factor that is referred to as the “guardian of the genome” and plays an important role in cancer development. P53 is active as a tetramer; the S100β homodimer binds to the intrinsically disordered C-terminus of p53, affecting its transcriptional activity. The p53/S100β complex is regarded as highly promising therapeutic target in cancer. It has been suggested that S100β exerts its oncogenic effects by altering the p53 oligomeric state. Our aim was to study the structures and oligomerization behavior of different p53/S100β complexes by electrospray ionization mass spectrometry (ESI-MS), cross-linking mass spectrometry (XL-MS), and surface plasmon resonance (SPR). For this, wild-type p53 and single amino acid variants, representing different oligomeric states of p53 (tetrameric wild-type, dimeric L344A variant, and monomeric L344P variant) were individually investigated regarding their binding behavior towards S100β. The stoichiometry of the different p53/S100β complexes were determined by ESI-MS showing that tetrameric, dimeric, and monomeric p53 variants all bind to an S100β dimer. In addition, XL-MS revealed the topologies of the p53/S100β complexes to be independent of p53’s oligomeric state. With SPR, the thermodynamic parameters were determined for S100β binding to tetrameric, dimeric or monomeric p53 variants. Our data prove that the S100β homodimer binds to different oligomeric states of p53 with identical stoichiometries and similar binding affinities. This emphasizes the need for alternative explanations to describe the molecular mechanisms underlying p53/S100β interaction.
Project description:p53 mutations are believed to correlate with poor patient survival, as mutations abolish the transcriptional function of wild-type p53 in the DNA damage response and mutant p53 gain-of-function activities enhance drug resistance. Moreover, p53 also exhibits non-transcriptional apoptotic activity with yet unclear in vivo relevance for tumor suppression and cancer therapy. We have generated mice expressing a unique p53 mutant (R178E, human R181E) that is DNA binding deficient without alterations in the global structure or DNA binding surface. The aim of this study is to use this new mouse model to demonstrate that a DNA binding-deficient p53 mutant can drive tumor development while retaining non-transcriptional apoptotic activities.