scholarly journals The Absence of Ser389 Phosphorylation in p53 Affects the Basal Gene Expression Level of Many p53-Dependent Genes and Alters the Biphasic Response to UV Exposure in Mouse Embryonic Fibroblasts

2008 ◽  
Vol 28 (6) ◽  
pp. 1974-1987 ◽  
Author(s):  
Wendy Bruins ◽  
Oskar Bruning ◽  
Martijs J. Jonker ◽  
Edwin Zwart ◽  
Tessa V. van der Hoeven ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Damage ◽  
Uv Irradiation ◽  
Target Genes ◽  
Late Response ◽  
Wild Type ◽  
Mouse Embryonic Fibroblasts ◽  
Embryonic Fibroblasts ◽  
Endogenous Gene ◽  
Cellular Processes

ABSTRACT Phosphorylation is important in p53-mediated DNA damage responses. After UV irradiation, p53 is phosphorylated specifically at murine residue Ser389. Phosphorylation mutant p53.S389A cells and mice show reduced apoptosis and compromised tumor suppression after UV irradiation. We investigated the underlying cellular processes by time-series analysis of UV-induced gene expression responses in wild-type, p53.S389A, and p53−/− mouse embryonic fibroblasts. The absence of p53.S389 phosphorylation already causes small endogenous gene expression changes for 2,253, mostly p53-dependent, genes. These genes showed basal gene expression levels intermediate to the wild type and p53−/−, possibly to readjust the p53 network. Overall, the p53.S389A mutation lifts p53-dependent gene repression to a level similar to that of p53−/− but has lesser effect on p53-dependently induced genes. In the wild type, the response of 6,058 genes to UV irradiation was strictly biphasic. The early stress response, from 0 to 3 h, results in the activation of processes to prevent the accumulation of DNA damage in cells, whereas the late response, from 12 to 24 h, relates more to reentering the cell cycle. Although the p53.S389A UV gene response was only subtly changed, many cellular processes were significantly affected. The early response was affected the most, and many cellular processes were phase-specifically lost, gained, or altered, e.g., induction of apoptosis, cell division, and DNA repair, respectively. Altogether, p53.S389 phosphorylation seems essential for many p53 target genes and p53-dependent processes.

scholarly journals Histone H3.3 regulates mitotic progression in mouse embryonic fibroblasts

2017 ◽  
Vol 95 (4) ◽  
pp. 491-499 ◽  
Author(s):  
Aysegul Ors ◽  
Christophe Papin ◽  
Bertrand Favier ◽  
Yohan Roulland ◽  
Defne Dalkara ◽  
...  
Keyword(s):  
Gene Expression ◽  
Large Scale ◽  
Target Genes ◽  
Global Gene Expression ◽  
Histone Variant ◽  
Mitotic Progression ◽  
Mouse Embryonic Fibroblasts ◽  
Embryonic Fibroblasts ◽  
Transcription Start Sites ◽  
Short Hairpin Rnas

H3.3 is a histone variant that marks transcription start sites as well as telomeres and heterochromatic sites on the genome. The presence of H3.3 is thought to positively correlate with the transcriptional status of its target genes. Using a conditional genetic strategy against H3.3B, combined with short hairpin RNAs against H3.3A, we essentially depleted all H3.3 gene expression in mouse embryonic fibroblasts. Following nearly complete loss of H3.3 in the cells, our transcriptomic analyses show very little impact on global gene expression or on the localization of histone variant H2A.Z. Instead, fibroblasts displayed slower cell growth and an increase in cell death, coincident with large-scale chromosome misalignment in mitosis and large polylobed or micronuclei in interphase cells. Thus, we conclude that H3.3 may have an important under-explored additional role in chromosome segregation, nuclear structure, and the maintenance of genome integrity.

scholarly journals Acetylation of Mouse p53 at Lysine 317 Negatively Regulates p53 Apoptotic Activities after DNA Damage

2006 ◽  
Vol 26 (18) ◽  
pp. 6859-6869 ◽  
Author(s):  
Connie Chao ◽  
Zhiqun Wu ◽  
Sharlyn J. Mazur ◽  
Helena Borges ◽  
Matteo Rossi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Damage ◽  
Posttranslational Modifications ◽  
P53 Protein ◽  
P53 Gene ◽  
Carboxyl Terminus ◽  
Mouse Embryonic Fibroblasts ◽  
Embryonic Fibroblasts ◽  
Doxorubicin Treatment ◽  
Lysine Residues

ABSTRACT Posttranslational modifications of p53, including phosphorylation and acetylation, play important roles in regulating p53 stability and activity. Mouse p53 is acetylated at lysine 317 by PCAF and at multiple lysine residues at the extreme carboxyl terminus by CBP/p300 in response to genotoxic and some nongenotoxic stresses. To determine the physiological roles of p53 acetylation at lysine 317, we introduced a Lys317-to-Arg (K317R) missense mutation into the endogenous p53 gene of mice. p53 protein accumulates to normal levels in p53K317R mouse embryonic fibroblasts (MEFs) and thymocytes after DNA damage. While p53-dependent gene expression is largely normal in p53K317R MEFs after various types of DNA damage, increased p53-dependent apoptosis was observed in p53K317R thymocytes, epithelial cells from the small intestine, and cells from the retina after ionizing radiation (IR) as well as in E1A/Ras-expressing MEFs after doxorubicin treatment. Consistent with these findings, p53-dependent expression of several proapoptotic genes was significantly increased in p53K317R thymocytes after IR. These findings demonstrate that acetylation at lysine 317 negatively regulates p53 apoptotic activities after DNA damage.

scholarly journals Phosphoproteomic Analysis Reveals Rio1-Related Protein Phosphorylation Changes in Response to UV Irradiation in Sulfolobus islandicus REY15A

2020 ◽  
Vol 11 ◽  
Author(s):  
Qihong Huang ◽  
Zijia Lin ◽  
Pengju Wu ◽  
Jinfeng Ni ◽  
Yulong Shen
Keyword(s):  
Dna Damage ◽  
Protein Phosphorylation ◽  
Uv Irradiation ◽  
Wild Type Strain ◽  
Wild Type ◽  
Cellular Processes ◽  
Sulfolobus Islandicus ◽  
Damage Response ◽  
In The Wild ◽  
Induced Changes

DNA damage response (DDR) in eukaryotes is largely regulated by protein phosphorylation. In archaea, many proteins are phosphorylated, however, it is unclear how the cells respond to DNA damage through global protein phosphorylation. We previously found that Δrio1, a Rio1 kinase homolog deletion strain of Sulfolobus islandicus REY15A, was sensitive to UV irradiation. In this study, we showed that Δrio1 grew faster than the wild type. Quantitative phosphoproteomic analysis of the wild type and Δrio1, untreated and irradiated with UV irradiation, revealed 562 phosphorylated sites (with a Ser/Thr/Tyr ratio of 65.3%/23.8%/10.9%) of 333 proteins in total. The phosphorylation levels of 35 sites of 30 proteins changed with >1.3-fold in the wild type strain upon UV irradiation. Interestingly, more than half of the UV-induced changes in the wild type did not occur in the Δrio1 strain, which were mainly associated with proteins synthesis and turnover. In addition, a protein kinase and several transcriptional regulators were differentially phosphorylated after UV treatment, and some of the changes were dependent on Rio1. Finally, many proteins involved in various cellular metabolisms exhibited Riol-related and UV-independent phosphorylation changes. Our results suggest that Rio1 is involved in the regulation of protein recycling and signal transduction in response to UV irradiation, and plays regulatory roles in multiple cellular processes in S. islandicus.

scholarly journals Regulation of c-Fos Gene Expression by NF-κB: A p65 Homodimer Binding Site in Mouse Embryonic Fibroblasts but Not Human HEK293 Cells

PLoS ONE ◽  
2013 ◽  
Vol 8 (12) ◽  
pp. e84062 ◽  
Author(s):  
Yu-Cheng Tu ◽  
Duen-Yi Huang ◽  
Shine-Gwo Shiah ◽  
Jang-Shiun Wang ◽  
Wan-Wan Lin
Keyword(s):  
Gene Expression ◽  
Binding Site ◽  
Hek293 Cells ◽  
Mouse Embryonic Fibroblasts ◽  
Embryonic Fibroblasts

scholarly journals Enrichment of Cxcl12 promoter with TET2: A possible link between promoter demethylation and enhanced gene expression in the absence of PARP-1

2019 ◽  
Vol 71 (3) ◽  
pp. 455-462
Author(s):  
Anja Tolic ◽  
Jovana Rajic ◽  
Marija Djordjevic ◽  
Milos Djordjevic ◽  
Svetlana Dinic ◽  
...  
Keyword(s):  
Gene Expression ◽  
Technological Development ◽  
Cpg Islands ◽  
Gene Induction ◽  
Dna Hypomethylation ◽  
Mouse Embryonic Fibroblasts ◽  
Embryonic Fibroblasts ◽  
Cxcl12 Expression ◽  
Knock Out ◽  
Parp 1

Previously, we described the link between C-X-C motif chemokine 12 (Cxcl12) gene induction and DNA hypomethylation in the absence of poly(ADP-ribose) polymerase 1 (PARP-1). We have now firmly established that demethylation is the primary cause of gene induction on the basis of Cxcl12 gene upregulation upon treatment with the demethylating agent 5-azacytidine (5-aza). Since the demethylation state of Cxcl12 is favored by PARP-1 absence, we investigated the presence of ten-eleven translocation (TET) proteins on the Cxcl12 promoter in order to corroborate the relationship between the demethylation process and increased gene expression that occurs in the absence of PARP-1. Analysis was performed on the promoter region within CpG islands of Cxcl12 from control mouse embryonic fibroblasts (NIH3T3) and PARP-1 knock-out mouse embryonic fibroblasts (PARP1-/-). The lack of PARP-1 increased the abundance of TET2 on the Cxcl12 promoter, suggesting that TET-mediated demethylation provoked by the absence of PARP-1 could account for the observed increased expression of this chemokine. Deciphering the regulation of DNA (de)methylation factors that control Cxcl12 expression may provide an additional therapeutic approach in pharmacological interventions where gene switching on or off based on targeted stimulation or inhibition is necessary. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 173020]

Involvement of the cgtA gene function in stimulation of DNA repair in Escherichia coli and Vibrio harveyi

Microbiology ◽  
2003 ◽  
Vol 149 (7) ◽  
pp. 1763-1770 ◽  
Author(s):  
Ryszard Zielke ◽  
Aleksandra Sikora ◽  
Rafał Dutkiewicz ◽  
Grzegorz Wegrzyn ◽  
Agata Czyż
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Dna Repair ◽  
Gene Product ◽  
Uv Irradiation ◽  
Vibrio Harveyi ◽  
Bacterial Species ◽  
Wild Type ◽  
E Coli ◽  
Stimulation Of

CgtA is a member of the Obg/Gtp1 subfamily of small GTP-binding proteins. CgtA homologues have been found in various prokaryotic and eukaryotic organisms, ranging from bacteria to humans. Nevertheless, despite the fact that cgtA is an essential gene in most bacterial species, its function in the regulation of cellular processes is largely unknown. Here it has been demonstrated that in two bacterial species, Escherichia coli and Vibrio harveyi, the cgtA gene product enhances survival of cells after UV irradiation. Expression of the cgtA gene was found to be enhanced after UV irradiation of both E. coli and V. harveyi. Moderate overexpression of cgtA resulted in higher UV resistance of E. coli wild-type and dnaQ strains, but not in uvrA, uvrB, umuC and recA mutant hosts. Overexpression of the E. coli recA gene in the V. harveyi cgtA mutant, which is very sensitive to UV light, restored the level of survival of UV-irradiated cells to the levels observed for wild-type bacteria. Moreover, the basal level of the RecA protein was lower in a temperature-sensitive cgtA mutant of E. coli than in the cgtA + strain, and contrary to wild-type bacteria, no significant increase in recA gene expression was observed after UV irradiation of this cgtA mutant. Finally, stimulation of uvrB gene transcription under these conditions was impaired in the V. harveyi cgtA mutant. All these results strongly suggest that the cgtA gene product is involved in DNA repair processes, most probably by stimulation of recA gene expression and resultant activation of RecA-dependent DNA repair pathways.

Role of the Hypoxia-Inducible Factor Pathway in Normal and Osteoarthritic Meniscus and in Mice after Destabilization of the Medial Meniscus

Cartilage ◽  
2020 ◽  
pp. 194760352095814
Author(s):  
Austin V. Stone ◽  
Richard F. Loeser ◽  
Michael F. Callahan ◽  
Margaret A. McNulty ◽  
David L. Long ◽  
...  
Keyword(s):  
Gene Expression ◽  
Target Genes ◽  
Medial Meniscus ◽  
Transforming Growth Factor ◽  
Hypoxia Inducible Factor ◽  
Early Time ◽  
Wild Type ◽  
Inflammatory Stimuli ◽  
Hif Pathway

Objective Meniscus injury and the hypoxia-inducible factor (HIF) pathway are independently linked to osteoarthritis pathogenesis, but the role of the meniscus HIF pathway remains unclear. We sought to identify and evaluate HIF pathway response in normal and osteoarthritic meniscus and to examine the effects of Epas1 (HIF-2α) insufficiency in mice on early osteoarthritis development. Methods Normal and osteoarthritic human meniscus specimens were obtained and used for immunohistochemical evaluation and cell culture studies for the HIF pathway. Meniscus cells were treated with pro-inflammatory stimuli, including interleukins (IL)-1β, IL-6, transforming growth factor (TGF)-α, and fibronectin fragments (FnF). Target genes were also evaluated with HIF-1α and HIF-2α (Epas1) overexpression and knockdown. Wild-type ( n = 36) and Epas1+/− ( n = 30) heterozygous mice underwent destabilization of the medial meniscus (DMM) surgery and were evaluated at 2 and 4 weeks postoperatively for osteoarthritis development using histology. Results HIF-1α and HIF-2α immunostaining and gene expression did not differ between normal and osteoarthritic meniscus. While pro-inflammatory stimulation significantly increased both catabolic and anabolic gene expression in the meniscus, HIF-1α and Epas1 expression levels were not significantly altered. Epas1 overexpression significantly increased Col2a1 expression. Both wild-type and Epas1+/− mice developed osteoarthritis following DMM surgery. There were no significant differences between genotypes at either time point. Conclusion The HIF pathway is likely not responsible for osteoarthritic changes in the human meniscus. Additionally, Epas1 insufficiency does not protect against osteoarthritis development in the mouse at early time points after DMM surgery. The HIF pathway may be more important for protection against catabolic stress.

KDM5D-mediated H3K4 demethylation is required for sexually dimorphic gene expression in mouse embryonic fibroblasts

2018 ◽  
Vol 165 (4) ◽  
pp. 335-342 ◽  
Author(s):  
Hayase Mizukami ◽  
Jun-Dal Kim ◽  
Saori Tabara ◽  
Weizhe Lu ◽  
Chulwon Kwon ◽  
...  
Keyword(s):  
Gene Expression ◽  
Sexually Dimorphic ◽  
Mouse Embryonic Fibroblasts ◽  
Embryonic Fibroblasts ◽  
Dimorphic Gene Expression

scholarly journals SUMO-1 Modification of Human Cytomegalovirus IE1/IE72

2002 ◽  
Vol 76 (6) ◽  
pp. 2990-2996 ◽  
Author(s):  
Mary L. Spengler ◽  
Karen Kurapatwinski ◽  
Adrian R. Black ◽  
Jane Azizkhan-Clifford
Keyword(s):  
Gene Expression ◽  
Protein Stability ◽  
Western Blotting ◽  
Human Cytomegalovirus ◽  
Posttranslational Modifications ◽  
Nuclear Architecture ◽  
Wild Type ◽  
Cellular Processes ◽  
Early Protein ◽  
Cycle Regulation

ABSTRACT Human cytomegalovirus (HCMV) immediate-early protein IE1/IE72 is involved in undermining many cellular processes including cell cycle regulation, apoptosis, nuclear architecture, and gene expression. The multifunctional nature of IE72 suggests that posttranslational modifications may modulate its activities. IE72 is a phosphoprotein and has intrinsic kinase activity (S. Pajovic, E. L. Wong, A. R. Black, and J. C. Azizkhan, Mol. Cell. Biol. 17:6459-6464, 1997). We now demonstrate that IE72 is covalently conjugated to the small ubiquitin-like modifier (SUMO-1). SUMO-1 is an 11.5-kDa protein that is conjugated to multiple proteins and has been reported to exhibit multiple effects, including modulation of protein stability, subcellular localization, and gene expression. A covalently modified protein migrating at ∼92 kDa, which is stabilized by a SUMO-1 hydrolase inhibitor, is revealed by Western blotting with anti-IE72 of lysates from cells infected with HCMV or cells expressing IE72. SUMO modification of IE72 was confirmed by immunoprecipitation with anti-IE72 and anti-SUMO-1 followed by Western blotting with anti-SUMO-1 and anti-IE72, respectively. Lysine 450 is within a sumoylation consensus site (I,V,L)KXE; changing lysine 450 to arginine by point mutation abolishes SUMO-1 modification of IE72. Inhibition of protein phosphatase 1 and 2A, which increases the phosphorylation of IE72, suppresses the formation of SUMO-1-IE72 conjugates. Both wild-type IE72 and IE72K450R localize to nuclear PML oncogenic domains and disrupt them. Studies of protein stability, transactivation, and complementation of IE72-deficient HCMV (CR208) have revealed no significant differences between wild-type IE72 and IE72K450R.

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