1
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Sumislawski P, Rotermund R, Klose S, Lautenbach A, Wefers AK, Soltwedel C, Mohammadi B, Jacobsen F, Mawrin C, Flitsch J, Saeger W. ACTH-secreting pituitary carcinoma with TP53, NF1, ATRX and PTEN mutations Case report and review of the literature. Endocrine 2022; 76:228-236. [PMID: 35171439 PMCID: PMC8986667 DOI: 10.1007/s12020-021-02954-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 11/14/2021] [Indexed: 02/06/2023]
Affiliation(s)
- Piotr Sumislawski
- Department of Neurosurgery, University Medical Center Hamburg-Eppendorf, Martinistr.52, 20246, Hamburg, Germany
| | - Roman Rotermund
- Department of Neurosurgery, University Medical Center Hamburg-Eppendorf, Martinistr.52, 20246, Hamburg, Germany
| | - Silke Klose
- Department of Internal Medicine/Endocrinology, Otto von Guericke Universität Magdeburg, Magdeburg, Germany
| | - Anne Lautenbach
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Annika K Wefers
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Mildred Scheel Cancer Career Center HaTriCS4, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Celina Soltwedel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Behnam Mohammadi
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Frank Jacobsen
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Martinistr, Hamburg, Germany
| | - Christian Mawrin
- Institute of Neuropathology, University of Magdeburg, Magdeburg, Germany
| | - Jörg Flitsch
- Department of Neurosurgery, University Medical Center Hamburg-Eppendorf, Martinistr.52, 20246, Hamburg, Germany
| | - Wolfgang Saeger
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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2
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Vadivel Gnanasundram S, Bonczek O, Wang L, Chen S, Fahraeus R. p53 mRNA Metabolism Links with the DNA Damage Response. Genes (Basel) 2021; 12:genes12091446. [PMID: 34573428 PMCID: PMC8465283 DOI: 10.3390/genes12091446] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 12/14/2022] Open
Abstract
Human cells are subjected to continuous challenges by different genotoxic stress attacks. DNA damage leads to erroneous mutations, which can alter the function of oncogenes or tumor suppressors, resulting in cancer development. To circumvent this, cells activate the DNA damage response (DDR), which mainly involves cell cycle regulation and DNA repair processes. The tumor suppressor p53 plays a pivotal role in the DDR by halting the cell cycle and facilitating the DNA repair processes. Various pathways and factors participating in the detection and repair of DNA have been described, including scores of RNA-binding proteins (RBPs) and RNAs. It has become increasingly clear that p53’s role is multitasking, and p53 mRNA regulation plays a prominent part in the DDR. This review is aimed at covering the p53 RNA metabolism linked to the DDR and highlights the recent findings.
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Affiliation(s)
- Sivakumar Vadivel Gnanasundram
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
- Correspondence: (S.V.G.); (R.F.)
| | - Ondrej Bonczek
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
- RECAMO, Masaryk Memorial Cancer Institute, Zluty Kopec 7, 656-53 Brno, Czech Republic
| | - Lixiao Wang
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
| | - Sa Chen
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
| | - Robin Fahraeus
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
- RECAMO, Masaryk Memorial Cancer Institute, Zluty Kopec 7, 656-53 Brno, Czech Republic
- Inserm UMRS1131, Institut de Genetique Moleculaire, Universite Paris 7, Hopital St Louis, F-75010 Paris, France
- International Centre for Cancer Vaccine Science, University of Gdansk, 80-822 Gdansk, Poland
- Correspondence: (S.V.G.); (R.F.)
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3
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Abstract
Deregulation of precursor mRNA splicing is associated with many illnesses and has been linked to age-related chronic diseases. Here we review recent progress documenting how defects in the machinery that performs intron removal and controls splice site selection contribute to cellular senescence and organismal aging. We discuss the functional association linking p53, IGF-1, SIRT1, and ING-1 splice variants with senescence and aging, and review a selection of splicing defects occurring in accelerated aging (progeria), vascular aging, and Alzheimer's disease. Overall, it is becoming increasingly clear that changes in the activity of splicing factors and in the production of key splice variants can impact cellular senescence and the aging phenotype.
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Affiliation(s)
- Mathieu Deschênes
- Department of Microbiology and Infectious DiseasesFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQuebecJ1E 4K8Canada
| | - Benoit Chabot
- Department of Microbiology and Infectious DiseasesFaculty of Medicine and Health SciencesUniversité de SherbrookeSherbrookeQuebecJ1E 4K8Canada
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4
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Zang Y, Shi Y, Liu K, Qiao L, Guo X, Chen D. Δ40p53 is involved in the inactivation of autophagy and contributes to inhibition of cell death in HCT116-Δ40p53 cells. Oncotarget 2017; 8:12754-12763. [PMID: 28061446 PMCID: PMC5355051 DOI: 10.18632/oncotarget.14460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 12/12/2016] [Indexed: 12/02/2022] Open
Abstract
Δ40p53 is an isoform of wild-type p53 (wtp53). Here, we assessed whether Δ40p53 has the same functions as wild-type p53 in the regulation of cell death and autophagy. First, we used HCT116 (p53+/+) and H1299 (p53-free) cells to produce two cell lines (HCT116-Δ40p53 and H1299-Δ40p53) that express exogenous Δ40p53 but not wtp53. By using these cell lines, we determined that Δ40p53 inhibited starvation-induced autophagy, as does wtp53. This inhibition arises from both Δ40p53 and wtp53 having 3′-5′ exonuclease activity, which reduces the levels of double-stranded RNA (dsRNA) and then inhibits PKR/eIF2α-induced autophagy in cells exposed to starvation. Like wtp53, the translocation of Δ40p53 to the nucleus increased in cells in response to Methyl methane sulfonate (MMS) treatment-induced DNA damage. Previous studies have shown that nuclear wtp53 can induce DRAM expression and DRAM-induced autophagy in cells in response to DNA damage, thereby contributing to apoptotic cell death as DRAM-induced autophagy is a pro-apoptotic factor. Here, nuclear Δ40p53 did not individually induce DRAM-induced autophagy and cell death in response to DNA damage. However, nuclear Δ40p53 inhibited wtp53-induced DRAM expression and cell death. Thus, Δ40p53 and wtp53 have 3′-5′ exonuclease activity and inhibit starvation-induced autophagy in the cytoplasm; however, nuclear Δ40p53 inhibits wtp53-induced cell death by impairing the transactivation activity of wtp53. Because wtp53 inhibits tumor and viral infection by inhibiting autophagy and promoting degradation of viral dsRNA, it is reasonable to believe that Δ40p53 has the similar functions. A deeper study of these functions of Δ40p53 is needed in the future.
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Affiliation(s)
- Yunjin Zang
- Capital Medical University affiliated Beijing You An Hospital, Beijing 100069, China.,Organ Transplantation Center, The Affiliated Hospital of Qingdao University, Shandong Province, 266003, China
| | - Ying Shi
- Beijing Institute of Hepatology, Beijing 100069, China.,Capital Medical University affiliated Beijing You An Hospital, Beijing 100069, China
| | - Kai Liu
- Beijing Institute of Hepatology, Beijing 100069, China.,Capital Medical University affiliated Beijing You An Hospital, Beijing 100069, China
| | - Luxin Qiao
- Beijing Institute of Hepatology, Beijing 100069, China.,Capital Medical University affiliated Beijing You An Hospital, Beijing 100069, China
| | - Xianghua Guo
- Beijing Institute of Hepatology, Beijing 100069, China.,Capital Medical University affiliated Beijing You An Hospital, Beijing 100069, China
| | - Dexi Chen
- Beijing Institute of Hepatology, Beijing 100069, China.,Capital Medical University affiliated Beijing You An Hospital, Beijing 100069, China.,Organ Transplantation Center, The Affiliated Hospital of Qingdao University, Shandong Province, 266003, China
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5
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Liu K, Zang Y, Guo X, Wei F, Yin J, Pang L, Chen D. The Δ133p53 Isoform Reduces Wtp53-induced Stimulation of DNA Pol γ Activity in the Presence and Absence of D4T. Aging Dis 2017; 8:228-239. [PMID: 28400988 PMCID: PMC5362181 DOI: 10.14336/ad.2016.0910] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 09/10/2016] [Indexed: 01/02/2023] Open
Abstract
The mitochondrial toxicity of nucleoside reverse transcriptase inhibitors (NRTIs) is due to the inhibition of mitochondrial DNA (mtDNA) polymerase γ (pol γ). Previous studies have shown that wild type p53 (wtp53) can interact with pol γ and mtDNA to enhance mitochondrial DNA base excision repair (mtBER) activity and increase the accuracy of DNA synthesis. The N-terminal transactivation domain and central specific DNA-binding domain of p53 play critical roles in the stimulation of BER. In this study, we identified the possible roles of wtp53, Δ40p53 and Δ133p53 in regulating mtDNA pol γ activity in cells with d4T treatment. The results show that Δ40p53 and Δ133p53 can exist in mitochondrial fragments and form polymers with themselves or wtp53. Unlike wtP53, Δ133p53 alone cannot increase DNA pol γ activity. More importantly, we found that Δ133p53 played a negative role in p53 stimulation of DNA pol γ activity when studied in d4T-treated and d4T-untreated mitochondrial extracts. Gel shift data also indicate that Δ40p53 and Δ133p53 cannot interact with APE. Wtp53 and Δ40p53 can act antagonize the effect of d4T inhibition of DNA pol γ activity. However, when wtp53 interacted with Δ133p53, DNA pol γ activity was significantly decreased. Conclusion: Δ133p53 negatively regulates p53’s stimulation of pol γ in the presence and absence of d4T.
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Affiliation(s)
- Kai Liu
- 1Beijing Institute of Hepatology, Beijing You An Hospital, Capital Medical University, Beijing 100069, China
| | - Yunjin Zang
- 2The Affiliated Hospital of Qingdao University, Organ Transplantation Center, Qingdao, Shandong 266003, China
| | - Xianghua Guo
- 1Beijing Institute of Hepatology, Beijing You An Hospital, Capital Medical University, Beijing 100069, China
| | - Feili Wei
- 1Beijing Institute of Hepatology, Beijing You An Hospital, Capital Medical University, Beijing 100069, China
| | - Jiming Yin
- 1Beijing Institute of Hepatology, Beijing You An Hospital, Capital Medical University, Beijing 100069, China
| | - Lijun Pang
- 1Beijing Institute of Hepatology, Beijing You An Hospital, Capital Medical University, Beijing 100069, China
| | - Dexi Chen
- 1Beijing Institute of Hepatology, Beijing You An Hospital, Capital Medical University, Beijing 100069, China
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6
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Abstract
p53 is a transcriptional regulator that responds to cellular stresses to suppress oncogenesis, but some of these responses can have unintended consequences that influence non-cancer-related aging processes. The impact of these consequences is not well understood-partly due to the many complex processes that influence p53 function and partly due to the vast array of processes that p53 affects. p53 has the potential to both accelerate and hinder cellular aging processes, which would likely have antithetical biological outcomes with regard to organismal aging. To accelerate aging, p53 induces apoptosis or cell cycle arrest as a prerequisite to cellular senescence; both can impair the mobilization of stem and progenitor cell populations. To suppress aging, p53 inhibits unregulated proliferation pathways that could lead to cellular senescence and a senescence-associated secretory phenotype (SASP), which creates a pro-inflammatory and degenerative tissue milieu. A review of mouse models supports both possibilities, highlighting the complexity of the p53 influence over organismal aging. A deeper knowledge of how p53 integrates and is integrated with various biological processes will improve our understanding of its influence over the aging process.
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Affiliation(s)
- Paul Hasty
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center at San Antonio, Texas 78245, USA.,Cancer Therapy & Research Center, University of Texas Health Science Center at San Antonio, Texas 78245, USA.,Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78245, USA
| | - Judith Campisi
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA.,Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Z Dave Sharp
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center at San Antonio, Texas 78245, USA.,Cancer Therapy & Research Center, University of Texas Health Science Center at San Antonio, Texas 78245, USA.,Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, Texas 78245, USA
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7
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Tournillon AS, López I, Malbert-Colas L, Findakly S, Naski N, Olivares-Illana V, Karakostis K, Vojtesek B, Nylander K, Fåhraeus R. p53 binds the mdmx mRNA and controls its translation. Oncogene 2016; 36:723-730. [PMID: 27375027 DOI: 10.1038/onc.2016.236] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 04/22/2016] [Accepted: 06/03/2016] [Indexed: 12/22/2022]
Abstract
MDMX and MDM2 are two nonredundant essential regulators of p53 tumor suppressor activity. MDM2 controls p53 expression levels, whereas MDMX is predominantly a negative regulator of p53 trans-activity. The feedback loops between MDM2 and p53 are well studied and involve both negative and positive regulation on transcriptional, translational and post-translational levels but little is known on the regulatory pathways between p53 and MDMX. Here we show that overexpression of p53 suppresses mdmx mRNA translation in vitro and in cell-based assays. The core domain of p53 binds the 5' untranslated region (UTR) of the mdmx mRNA in a zinc-dependent manner that together with a trans-suppression domain located in p53 N-terminus controls MDMX synthesis. This interaction can be visualized in the nuclear and cytoplasmic compartment. Fusion of the mdmx 5'UTR to the ovalbumin open reading frame leads to suppression of ovalbumin synthesis. Interestingly, the transcription inactive p53 mutant R273H has a different RNA-binding profile compared with the wild-type p53 and differentiates the synthesis of MDMX isoforms. This study describes p53 as a trans-suppressor of the mdmx mRNA and adds a further level to the intricate feedback system that exist between p53 and its key regulatory factors and emphasizes the important role of mRNA translation control in regulating protein expression in the p53 pathway.
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Affiliation(s)
- A-S Tournillon
- Equipe Labellisée la Ligue Contre le Cancer, Institut National de la Santé et de la Recherche Médicale UMR1162, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St Louis, Paris, France
| | - I López
- Equipe Labellisée la Ligue Contre le Cancer, Institut National de la Santé et de la Recherche Médicale UMR1162, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St Louis, Paris, France
| | - L Malbert-Colas
- Equipe Labellisée la Ligue Contre le Cancer, Institut National de la Santé et de la Recherche Médicale UMR1162, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St Louis, Paris, France
| | - S Findakly
- Equipe Labellisée la Ligue Contre le Cancer, Institut National de la Santé et de la Recherche Médicale UMR1162, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St Louis, Paris, France
| | - N Naski
- Equipe Labellisée la Ligue Contre le Cancer, Institut National de la Santé et de la Recherche Médicale UMR1162, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St Louis, Paris, France
| | - V Olivares-Illana
- Instituto de Física, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
| | - K Karakostis
- Equipe Labellisée la Ligue Contre le Cancer, Institut National de la Santé et de la Recherche Médicale UMR1162, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St Louis, Paris, France
| | - B Vojtesek
- RECAMO, Masaryk Memorial Cancer Institute, Brno, Czech Republic
| | - K Nylander
- Department of Medical Biosciences, Umeå University, Umeå, Sweden
| | - R Fåhraeus
- Equipe Labellisée la Ligue Contre le Cancer, Institut National de la Santé et de la Recherche Médicale UMR1162, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St Louis, Paris, France.,RECAMO, Masaryk Memorial Cancer Institute, Brno, Czech Republic.,Department of Medical Biosciences, Umeå University, Umeå, Sweden
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8
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Li M, Pehar M, Liu Y, Bhattacharyya A, Zhang SC, O'Riordan KJ, Burger C, D'Adamio L, Puglielli L. The amyloid precursor protein (APP) intracellular domain regulates translation of p44, a short isoform of p53, through an IRES-dependent mechanism. Neurobiol Aging 2015; 36:2725-36. [PMID: 26174856 DOI: 10.1016/j.neurobiolaging.2015.06.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 06/15/2015] [Accepted: 06/15/2015] [Indexed: 01/01/2023]
Abstract
p44 is a short isoform of the tumor suppressor protein p53 that is regulated in an age-dependent manner. When overexpressed in the mouse, it causes a progeroid phenotype that includes premature cognitive decline, synaptic defects, and hyperphosphorylation of tau. The hyperphosphorylation of tau has recently been linked to the ability of p44 to regulate transcription of relevant tau kinases. Here, we report that the amyloid precursor protein (APP) intracellular domain (AICD), which results from the processing of the APP, regulates translation of p44 through a cap-independent mechanism that requires direct binding to the second internal ribosome entry site (IRES) of the p53 mRNA. We also report that AICD associates with nucleolin, an already known IRES-specific trans-acting factor that binds with p53 IRES elements and regulates translation of p53 isoforms. The potential biological impact of our findings was assessed in a mouse model of Alzheimer's disease. In conclusion, our study reveals a novel aspect of AICD and p53/p44 biology and provides a possible molecular link between APP, p44, and tau.
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9
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Mlynarczyk C, Fåhraeus R. Endoplasmic reticulum stress sensitizes cells to DNA damage-induced apoptosis through p53-dependent suppression of p21CDKN1A. Nat Commun 2014; 5. [DOI: 10.1038/ncomms6067] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 08/25/2014] [Indexed: 12/19/2022] Open
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10
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Pehar M, Ko MH, Li M, Scrable H, Puglielli L. P44, the 'longevity-assurance' isoform of P53, regulates tau phosphorylation and is activated in an age-dependent fashion. Aging Cell 2014; 13:449-56. [PMID: 24341977 PMCID: PMC4032616 DOI: 10.1111/acel.12192] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2013] [Indexed: 11/30/2022] Open
Abstract
p44 is a short isoform of p53 with 'longevity-assurance' activity. Overexpression of p44 in the mouse (p44(+/+) transgenic mice) causes a progeroid phenotype that mimics an accelerated form of aging. The phenotype includes abnormal phosphorylation of the microtubule-binding protein tau, synaptic deficits, and cognitive decline. Genetic engineering demonstrated that the phosphorylation status of tau acts upstream of the synaptic deficits. Here, we provide evidence that p44 promotes the phosphorylation of tau in the mouse. Specifically, we show that p44 binds to the promoter of tau kinases Dyrk1A, GSK3β, Cdk5, p35, and p39 and activates their transcription. The upregulation of the above kinases is followed by increased phosphorylation of tau. Finally, we show that p44 is preferentially found in the nucleus and that its levels increase with age in the mouse brain. Taken together, these results suggest that an imbalance in the p53:p44 ratio might be involved with the altered tau metabolism that characterizes aging.
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Affiliation(s)
- Mariana Pehar
- Department of Medicine University of Wisconsin‐Madison 2500 Overlook TerraceMadison WI 53705 USA
| | - Mi Hee Ko
- Department of Medicine University of Wisconsin‐Madison 2500 Overlook TerraceMadison WI 53705 USA
| | - Mi Li
- Department of Medicine University of Wisconsin‐Madison 2500 Overlook TerraceMadison WI 53705 USA
| | - Heidi Scrable
- Robert and Arlene Kogod Center on Aging Division of Experimental Pathology Mayo Clinic Rochester MN 55905USA
| | - Luigi Puglielli
- Department of Medicine University of Wisconsin‐Madison 2500 Overlook TerraceMadison WI 53705 USA
- Geriatric Research Education Clinical Center VA Medical Center 2500 Overlook Terrace Madison WI 53705USA
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11
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12
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Hasty P, Christy BA. p53 as an intervention target for cancer and aging. Pathobiol Aging Age Relat Dis 2013; 3:22702. [PMID: 24124625 PMCID: PMC3794078 DOI: 10.3402/pba.v3i0.22702] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 09/13/2013] [Accepted: 09/13/2013] [Indexed: 12/30/2022]
Abstract
p53 is well known for suppressing tumors but could also affect other aging processes not associated with tumor suppression. As a transcription factor, p53 responds to a variety of stresses to either induce apoptosis (cell death) or cell cycle arrest (cell preservation) to suppress tumor development. Yet, the effect p53 has on the non-cancer aspects of aging is complicated and not well understood. On one side, p53 could induce cellular senescence or apoptosis to suppress cancer but as an unintended consequence enhance the aging process especially if these responses diminish stem and progenitor cell populations. But on the flip side, p53 could reduce growth and growth-related stress to enable cell survival and ultimately delay the aging process. A better understanding of diverse functions of p53 is essential to elucidate its influences on the aging process and the possibility of targeting p53 or p53 transcriptional targets to treat cancer and ameliorate general aging.
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Affiliation(s)
- Paul Hasty
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA ; Cancer Therapy & Research Center, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA ; Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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13
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Segreto HRC, Oshima CTF, Franco MF, Silva MRR, Egami MI, Teixeira VPC, Segreto RA. Phosphorylation and cytoplasmic localization of MAPK p38 during apoptosis signaling in bone marrow granulocytes of mice irradiated in vivo and the role of amifostine in reducing these effects. Acta Histochem 2011; 113:300-7. [PMID: 20074782 DOI: 10.1016/j.acthis.2009.12.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 11/27/2009] [Accepted: 11/30/2009] [Indexed: 01/14/2023]
Abstract
We studied p38 phosphorylation and its intracellular localization during p53 and Puma (a p53 upregulated modulator of apoptosis) apoptotic signaling pathway in bone marrow granulocytes in mice irradiated in vivo and the role of the radioprotector amifostine in ameliorating these responses. Sixty-four C57BL mice were randomly assigned in two non-irradiated (Ami-/rad- and Ami+/rad-) and two irradiated (Ami-/rad+ and Ami+/rad+) groups. Animals received 400mg/kg of amifostine i.p. 30 min prior to a single whole body radiation dose of 7Gy. The experiments were performed using immunohistochemistry for caspase-3, cleaved caspase-3, p53, p-p53 (Ser 15), Puma, p38 and p-p38 (Thr 180/Tyr 182) protein expression. In addition transmission electron microscopy was used for ultrastructural characterization of apoptosis. Data showed that: (i) amifostine significantly reduced the number of apoptotic cells, (ii) p-p53 and Puma proteins were strongly immunostained in granulocytes after irradiation (Ami-/rad+), (iii) amifostine decreased the immunostaining of the proteins (Ami+/rad+), (iv) p38 was immunolocalized in physiological conditions in the nucleus and cytoplasm of granulocytes and neither radiation nor amifostine changed the protein immunostaining or its subcellular distribution, but influenced its activation, (v) radiation-induced p38 phosphorylation and its cytoplasmic accumulation during apoptosis signaling in granulocytes after whole body high radiation dose and amifostine markedly reduced these effects.
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Affiliation(s)
- Helena R C Segreto
- Department of Clinical and Experimental Oncology, Radiotherapy Division, Federal University of São Paulo, UNIFESP, Rua Pascal 778, São Paulo, SP, Brazil.
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14
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Abstract
OBJECTIVE Investigating the dynamics of pancreatic β-cell mass is critical for developing strategies to treat both type 1 and type 2 diabetes. p53, a key regulator of the cell cycle and apoptosis, has mostly been a focus of investigation as a tumor suppressor. Although p53 alternative transcripts can modulate p53 activity, their functions are not fully understood. We hypothesized that β-cell proliferation and glucose homeostasis were controlled by Δ40p53, a p53 isoform lacking the transactivation domain of the full-length protein that modulates total p53 activity and regulates organ size and life span in mice. RESEARCH DESIGN AND METHODS We phenotyped metabolic parameters in Δ40p53 transgenic (p44tg) mice and used quantitative RT-PCR, Western blotting, and immunohistochemistry to examine β-cell proliferation. RESULTS Transgenic mice with an ectopic p53 gene encoding Δ40p53 developed hypoinsulinemia and glucose intolerance by 3 months of age, which worsened in older mice and led to overt diabetes and premature death from ∼14 months of age. Consistent with a dramatic decrease in β-cell mass and reduced β-cell proliferation, lower expression of cyclin D2 and pancreatic duodenal homeobox-1, two key regulators of proliferation, was observed, whereas expression of the cell cycle inhibitor p21, a p53 target gene, was increased. CONCLUSIONS These data indicate a significant and novel role for Δ40p53 in β-cell proliferation with implications for the development of age-dependent diabetes.
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Affiliation(s)
- Charlotte Hinault
- Research Division, Joslin Diabetes Center and Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Dan Kawamori
- Research Division, Joslin Diabetes Center and Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Chong Wee Liew
- Research Division, Joslin Diabetes Center and Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Bernhard Maier
- Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jiang Hu
- Research Division, Joslin Diabetes Center and Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
| | | | - Raghavendra G. Mirmira
- Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana
| | - Heidi Scrable
- Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Rohit N. Kulkarni
- Research Division, Joslin Diabetes Center and Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts
- Corresponding author: Rohit N. Kulkarni,
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15
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Grover R, Candeias MM, Fåhraeus R, Das S. p53 and little brother p53/47: linking IRES activities with protein functions. Oncogene 2009; 28:2766-72. [DOI: 10.1038/onc.2009.138] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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16
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Abstract
George Williams' antagonistic pleiotropy theory of aging proposes that cellular damage and organismal aging are caused by pleiotrophic genes, or genes with multiple phenotypic effects [Williams, G.C., 1957. Pleiotropy, natural selection, and the evolution of senescence. Evolution 11, 398-411]. According to this theory, genes that exhibit antagonistic pleiotropy increase the odds of successful reproduction early in life, but have deleterious effects later in life. The tumor suppressor p53 confers protection against cancer (and death) by interrupting the abnormal proliferation of cells. When control of proliferation is applied to normal stem cells, however, it can impair tissue homeostasis and accelerate aging. We use data from recently developed models of accelerated aging in mice to determine if the deleterious effects of p53 on aging reflect antagonistic pleiotropy of the p53 gene or are attributable to genes that can modify p53 activity but are evolving independently.
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17
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Vorovich E, Ratovitski EA. Dual regulation of TERT activity through transcription and splicing by DeltaNP63alpha. Aging (Albany NY) 2008; 1:58-67. [PMID: 20157588 PMCID: PMC2815765 DOI: 10.18632/aging.100003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2008] [Accepted: 12/05/2008] [Indexed: 01/21/2023]
Abstract
P53 homolog p63 was shown to play a
role in premature ageing phenotype found in mouse models through regulation
of the replicative senescence. We previously showed that the forced ΔNp63α expression
decreased the SIRT1 protein levels, and induced the replicative senescence
of human keratinocytes, while the ectopic SIRT1 expression decreased the
senescence. Using the ΔNp63α overexpressing
and p63-/+ heterozygous mice, we found that ΔNp63α induced the mTERT
promoter activation through the down regulation of the SIRT1 protein
levels, inactivation of p53 deacetylation, decrease of the p53/Sp1
protein-protein interaction, and the overall induction of mTERT
transcription regulation. In the same time, by a forming of protein-protein
complexes with the ABBP1, ΔNp63α induced the mTERT
RNA splicing leading to an increasing expression of spliced mTERT isoforms
playing a role of dominant-negative inhibitors of mTERT activity and
therefore decreasing the levels of TERT activity in mouse epidermal
keratinocytes. The overall effect of the ΔNp63α overexpression
resulted in decrease in telomerase activity and increase in replicative
senescence observed in mouse keratinocytes. This dual molecular mechanism
of telomerase regulation might underline the previously shown effect of ΔNp63α on premature
ageing phenotype.
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Affiliation(s)
- Esther Vorovich
- Department of Dermatology, The Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
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18
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Li H, Mitchell JR, Hasty P. DNA double-strand breaks: a potential causative factor for mammalian aging? Mech Ageing Dev 2008; 129:416-24. [PMID: 18346777 PMCID: PMC2517577 DOI: 10.1016/j.mad.2008.02.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 01/11/2008] [Accepted: 02/07/2008] [Indexed: 11/30/2022]
Abstract
Aging is a pleiotropic and stochastic process influenced by both genetics and environment. As a result the fundamental underlying causes of aging are controversial and likely diverse. Genome maintenance and in particular the repair of DNA damage is critical to ensure longevity needed for reproduction and as a consequence imperfections or defects in maintaining the genome may contribute to aging. There are many forms of DNA damage with double-strand breaks (DSBs) being the most toxic. Here we discuss DNA DSBs as a potential causative factor for aging including factors that generate DNA DSBs, pathways that repair DNA DSBs, consequences of faulty or failed DSB repair and how these consequences may lead to age-dependent decline in fitness. At the end we compare mouse models of premature aging that are defective for repairing either DSBs or UV light-induced lesions. Based on these comparisons we believe the basic mechanisms responsible for their aging phenotypes are fundamentally different demonstrating the complex and pleiotropic nature of this process.
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Affiliation(s)
- Han Li
- Department of Molecular Medicine, Institute of Biotechnology, University of Texas Health Science Center, 15355 Lambda Drive, San Antonio, TX 78245-3207, USA.
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19
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Scrable H, Medrano S, Ungewitter E. Running on empty: how p53 controls INS/IGF signaling and affects life span. Exp Gerontol 2008; 44:93-100. [PMID: 18598747 DOI: 10.1016/j.exger.2008.05.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Revised: 05/21/2008] [Accepted: 05/27/2008] [Indexed: 10/21/2022]
Abstract
In higher organisms dependent on the regenerative ability of tissue stem cells to maintain tissue integrity throughout adulthood, the failure of stem cells to replace worn out, dead, or damaged cells is seen as one mechanism that limits life span. In these organisms, tumor suppressors such as p53 are central participants in the control of longevity because they regulate stem cell proliferation. Several recent reports have identified p53 as a longevity gene in organisms such as Caenorhabditis elegans and Drosophila melanogaster, which lack proliferative stem cells in all but the germline and have relatively short life spans. This has forced us to reevaluate the role of p53 in the control of life span. We discuss how p53 might regulate longevity in both long- and short-lived species by controlling the activity of insulin-like molecules that operate in proliferating and non-proliferating compartments of adult somatic tissues. We also discuss the hierarchical structure of life span regulation where loss of p53 has life span extending effects. Finally, we suggest a molecular mechanism by which p53 might facilitate the response to severe nutrient deprivation that allows metabolically active cells to survive periods of starvation. Paradoxically, loss of p53 function in these cells would compromise life span.
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Affiliation(s)
- Heidi Scrable
- University of Virginia, Department of Neuroscience, Charlottesville, Virginia, USA.
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20
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Schmid G, Kramer MP, Maurer M, Wandl S, Wesierska-Gadek J. Cellular and organismal ageing: Role of the p53 tumor suppressor protein in the induction of transient and terminal senescence. J Cell Biochem 2008; 101:1355-69. [PMID: 17471501 DOI: 10.1002/jcb.21383] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In recent years, an impact of the p53 tumor suppressor protein in the processes of cellular and organismal ageing became evident. First hints were found in model organisms like Saccharomyces cerevisiae, Caenorhabditis elegans, and Drosophila melanogaster where a clear connection between ageing phenotypes and pathways that are regulated by p53, were found. Interestingly, pathways that are central to the ageing process are usually also involved in energy metabolism and are highly conserved throughout evolution. This also supports the long known empiric finding that caloric restriction has a positive impact on the life span of a wide variety of organisms. Within the last years, on the molecular level, an involvement of the insulin-like growth factor and of the histone deacetylase SRIT1 could be shown. Insight on the impact of p53 on ageing at the organismal level came from mice expressing aberrant forms of the p53 protein. Obviously, the balance of the full length p53 protein and of the shorter p44/DeltaNp53 isomer bear a strong impact on ageing. The shorter isoform regulates full length p53 and in cases where there is too much of the longer isoform, this leads to elevated apoptosis resulting in decreased tumor incidence but also in premature ageing due to exhaustion of the renewal potential. Therefore, modulating the expression of the truncated p53 isoform accordingly, might lead to increased health-span and elevated life-span.
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Affiliation(s)
- Gerald Schmid
- Cell Cycle Regulation Group, Department of Medicine I, Division: Institute of Cancer Research, Medical University of Vienna, Vienna, Austria
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21
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Brazhnik P, Kohn KW. HAUSP-regulated switch from auto- to p53 ubiquitination by Mdm2 (in silico discovery). Math Biosci 2007; 210:60-77. [PMID: 17585950 DOI: 10.1016/j.mbs.2007.05.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2006] [Revised: 12/19/2006] [Accepted: 05/15/2007] [Indexed: 11/17/2022]
Abstract
Stability of the 'guardian of the genome' tumor suppressor protein p53 is regulated predominantly through its ubiquitination. The ubiquitin-specific protease HAUSP plays an important role in this process. Recent experiments showed that p53 demonstrates a differential response to changes in HAUSP which nature and significance are not understood yet. Here a data-driven mathematical model of the Mdm2-mediated p53 ubiquitination network is presented which offers an explanation for the cause of such a response. The model predicts existence of the HAUSP-regulated switch from auto- to p53 ubiquitination by Mdm2. This switch suggests a potential role of HAUSP as a downstream target of stress signals in cells. The model accounts for a significant amount of experimental data, makes predictions for some rate constants, and can serve as a building block for the larger model describing a complex dynamic response of p53 to cellular stresses.
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Affiliation(s)
- Paul Brazhnik
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, United States.
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22
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Costantini C, Ko M, Jonas M, Puglielli L. A reversible form of lysine acetylation in the ER and Golgi lumen controls the molecular stabilization of BACE1. Biochem J 2007; 407:383-95. [PMID: 17425515 PMCID: PMC2275071 DOI: 10.1042/bj20070040] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The lipid second messenger ceramide regulates the rate of beta cleavage of the Alzheimer's disease APP (amyloid precursor protein) by affecting the molecular stability of the beta secretase BACE1 (beta-site APP cleaving enzyme 1). Such an event is stimulated in the brain by the normal process of aging, and is under the control of the general aging programme mediated by the insulin-like growth factor 1 receptor. In the present study we report that BACE1 is acetylated on seven lysine residues of the N-terminal portion of the nascent protein. This process involves lysine acetylation in the lumen of the ER (endoplasmic reticulum) and is followed by deacetylation in the lumen of the Golgi apparatus, once the protein is fully mature. We also show that specific enzymatic activities acetylate (in the ER) and deacetylate (in the Golgi apparatus) the lysine residues. This process requires carrier-mediated translocation of acetyl-CoA into the ER lumen and is stimulated by ceramide. Site-directed mutagenesis indicates that lysine acetylation is necessary for nascent BACE1 to leave the ER and move ahead in the secretory pathway, and for the molecular stabilization of the protein.
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Affiliation(s)
- Claudio Costantini
- *Department of Medicine, University of Madison-Wisconsin, Madison, WI 53705, U.S.A
| | - Mi Hee Ko
- *Department of Medicine, University of Madison-Wisconsin, Madison, WI 53705, U.S.A
| | - Mary Cabell Jonas
- *Department of Medicine, University of Madison-Wisconsin, Madison, WI 53705, U.S.A
- †Cellular and Molecular Biology Program, University of Wisconsin-Madison, Madison, WI 53705, U.S.A
| | - Luigi Puglielli
- *Department of Medicine, University of Madison-Wisconsin, Madison, WI 53705, U.S.A
- †Cellular and Molecular Biology Program, University of Wisconsin-Madison, Madison, WI 53705, U.S.A
- ‡Geriatric Research Education Clinical Center, VA Medical Center, Madison, Wisconsin 53705, U.S.A
- To whom correspondence should be addressed (email )
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23
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Olsson A, Manzl C, Strasser A, Villunger A. How important are post-translational modifications in p53 for selectivity in target-gene transcription and tumour suppression? Cell Death Differ 2007; 14:1561-75. [PMID: 17627286 DOI: 10.1038/sj.cdd.4402196] [Citation(s) in RCA: 150] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
A number of elegant studies exploring the consequences of expression of various mutant forms of p53 in mice have been published over the last years. The results and conclusions drawn from these studies often contradict results previously obtained in biochemical assays and cell biology studies, questioning their relevance for p53 function in vivo. Owing to the multitude of post-translational modifications imposed on p53, however, the in vivo validation of their relevance for proper protein function and tumour suppression is constantly lagging behind new biochemical discoveries. Nevertheless, mouse genetics presents again its enormous power. Despite being relatively slow and tedious, it has become indispensable for researchers to sort out the wheat from the chaff in an endless sea of publications on p53.
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Affiliation(s)
- A Olsson
- Division of Developmental Immunology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
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24
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Puglielli L. Aging of the brain, neurotrophin signaling, and Alzheimer's disease: is IGF1-R the common culprit? Neurobiol Aging 2007; 29:795-811. [PMID: 17313996 PMCID: PMC2387053 DOI: 10.1016/j.neurobiolaging.2007.01.010] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2006] [Revised: 09/21/2006] [Accepted: 01/13/2007] [Indexed: 12/26/2022]
Abstract
The last decade has revealed that the lifespan of an organism can be modulated by the signaling pathway that acts downstream of the insulin/insulin-like growth factor 1 receptors (IR/IGF1-R), indicating that there is a "program" that drives the process of aging. New results have now linked the same pathway to the neurogenic capacities of the aging brain, to neurotrophin signaling, and to the molecular pathogenesis of Alzheimer's disease. Therefore, a common signaling cascade now seems to link aging to age-associated pathologies of the brain, suggesting that pharmacologic approaches aimed at the modulation of this pathway can serve to delay the onset of age-associated disorders and improve the quality of life. Work from a wide range of fields performed with different approaches has already identified some of the signaling molecules that act downstream of IGF1-R, and has revealed that a delicate checkpoint exists to balance excessive growth/"immortality" and reduced growth/"senescence" of a cell. Future research will determine how far the connection goes and how much of it we can influence.
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Affiliation(s)
- Luigi Puglielli
- Department of Medicine, University of Wisconsin-Madison, and Geriatric Research Education Clinical Center, VA Medical Center, VAH-GRECC 11G, 2500 Overlook Terrace, Madison, WI 53705, USA.
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25
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Abstract
One of the most frequently mutated genes in human cancers, tumour suppressor p53 (TP53), can induce cell-cycle arrest and apoptosis. The apoptotic function of p53 is tightly linked to its tumour-suppression function and the efficacy of many cancer therapies depends on this. The identification of a new family of proteins, known as ASPPs (ankyrin-repeat-, SH3-domain- and proline-rich-region-containing proteins), has led to the discovery of a novel mechanism that selectively regulates the apoptotic function, but not the cell-cycle-arrest function, of p53, and gives an insight into how p53 responds to different stress signals. ASPPs might be new molecular targets for cancer therapy.
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Affiliation(s)
- Giuseppe Trigiante
- Ludwig Institute for Cancer Research, Courtauld Building, 91 Riding House Street, London W1W 7BS, UK
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26
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Abstract
There is compelling evidence for the central role of the p53 pathway in human neoplasia but, despite an enormous literature, the clinical utility of assessing this pathway remains ambiguous. Even simple questions about the assessment of p53 status in clinical samples remain unanswered and the literature is confusing and often contradictory. The p53 pathway is certainly complicated and the biochemical mechanisms for regulating the function of p53 and its downstream consequences are rabbinical in complexity. This perspective considers this complexity and the reasons why establishing the true utility of clinical assessment of p53 has proven to be so difficult. Indeed, recent observations regarding the existence of alternate splice variants of p53, the complexity of p53 regulation, and the existence of allelic variants of p53 and its regulators with distinct functionality makes the situation even more complex. Problems with the available assays are considered and the need to consider an array of methodological issues is emphasized. Newer strategies including analysis of the expression of downstream targets of p53 and the use of threshold strategies to measure p53 protein may provide more robust measures of the p53 pathway in clinical settings, perhaps coupled with cheap sequencing-based approaches for mutation (and polymorphism) detection. However, progress will only be made if these methodological issues are resolved and robust assays are performed in the context of appropriately powered studies in clinical trial settings.
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Affiliation(s)
- Peter A Hall
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, U Floor, Belfast City Hospital, Belfast, BT9 7AB, Northern Ireland, UK.
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