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Zhou S, Zhou Y, Zhong W, Su Z, Qin Z. Involvement of protein L-isoaspartyl methyltransferase in the physiopathology of neurodegenerative diseases: Possible substrates associated with synaptic function. Neurochem Int 2023; 170:105606. [PMID: 37657764 DOI: 10.1016/j.neuint.2023.105606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 08/11/2023] [Accepted: 08/29/2023] [Indexed: 09/03/2023]
Abstract
Synaptic dysfunction is a typical pathophysiologic change in neurodegenerative diseases (NDs) such as Alzheimer's disease (AD), Parkinson's disease (PD), Hintington's disease (HD) and amyotrophic lateral sclerosis (ALS), which involves protein post-translational modifications (PTMs) including L-isoaspartate (L-isoAsp) formed by isomerization of aspartate or deamidation of asparagine. The formation of L-isoAsp could be repaired by protein L-isoaspartyl methyltransferase (PIMT). Some synaptic proteins have been identified as PIMT potential substrates and play an essential role in ensuring synaptic function. In this review, we discuss the role of certain synaptic proteins as PIMT substrates in neurodegenerative disease, thus providing therapeutic synapse-centered targets for the treatment of NDs.
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Affiliation(s)
- Sirui Zhou
- Department of Anatomy, School of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Yancheng Zhou
- Department of Anatomy, School of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Wanyu Zhong
- Department of Anatomy, School of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Zhonghao Su
- Department of Febrile Disease, School of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
| | - Zhenxia Qin
- Department of Anatomy, School of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
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2
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Bin-Jumah MN, Nadeem MS, Gilani SJ, Al-Abbasi FA, Ullah I, Alzarea SI, Ghoneim MM, Alshehri S, Uddin A, Murtaza BN, Kazmi I. Genes and Longevity of Lifespan. Int J Mol Sci 2022; 23:ijms23031499. [PMID: 35163422 PMCID: PMC8836117 DOI: 10.3390/ijms23031499] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 01/04/2022] [Accepted: 01/26/2022] [Indexed: 12/12/2022] Open
Abstract
Aging is a complex process indicated by low energy levels, declined physiological activity, stress induced loss of homeostasis leading to the risk of diseases and mortality. Recent developments in medical sciences and an increased availability of nutritional requirements has significantly increased the average human lifespan worldwide. Several environmental and physiological factors contribute to the aging process. However, about 40% human life expectancy is inherited among generations, many lifespan associated genes, genetic mechanisms and pathways have been demonstrated during last decades. In the present review, we have evaluated many human genes and their non-human orthologs established for their role in the regulation of lifespan. The study has included more than fifty genes reported in the literature for their contributions to the longevity of life. Intact genomic DNA is essential for the life activities at the level of cell, tissue, and organ. Nucleic acids are vulnerable to oxidative stress, chemotherapies, and exposure to radiations. Efficient DNA repair mechanisms are essential for the maintenance of genomic integrity, damaged DNA is not replicated and transferred to next generations rather the presence of deleterious DNA initiates signaling cascades leading to the cell cycle arrest or apoptosis. DNA modifications, DNA methylation, histone methylation, histone acetylation and DNA damage can eventually lead towards apoptosis. The importance of calorie restriction therapy in the extension of lifespan has also been discussed. The role of pathways involved in the regulation of lifespan such as DAF-16/FOXO (forkhead box protein O1), TOR and JNK pathways has also been particularized. The study provides an updated account of genetic factors associated with the extended lifespan and their interactive contributory role with cellular pathways.
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Affiliation(s)
- May Nasser Bin-Jumah
- Biology Department, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia;
- Environment and Biomaterial Unit, Health Sciences Research Center, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia
| | - Muhammad Shahid Nadeem
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
- Correspondence: (M.S.N.); (I.K.)
| | - Sadaf Jamal Gilani
- Department of Basic Health Sciences, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia;
| | - Fahad A. Al-Abbasi
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
| | - Inam Ullah
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore 54000, Pakistan;
| | - Sami I. Alzarea
- Department of Pharmacology, College of Pharmacy, Jouf University, Sakaka 72341, Saudi Arabia;
| | - Mohammed M. Ghoneim
- Department of Pharmacy Practice, College of Pharmacy, AlMaarefa University, Ad Diriyah 13713, Saudi Arabia;
| | - Sultan Alshehri
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia;
| | - Aziz Uddin
- Department of Biotechnology and Genetic Engineering, Hazara University, Mansehra 21300, Pakistan;
| | - Bibi Nazia Murtaza
- Department of Zoology, Abbottabad University of Science and Technology (AUST), Abbottabad 22310, Pakistan;
| | - Imran Kazmi
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
- Correspondence: (M.S.N.); (I.K.)
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Kimura Y, Komatsu T, Yanagi K, Hanaoka K, Ueno T, Terai T, Kojima H, Okabe T, Nagano T, Urano Y. Development of Chemical Tools to Monitor and Control Isoaspartyl Peptide Methyltransferase Activity. Angew Chem Int Ed Engl 2016; 56:153-157. [DOI: 10.1002/anie.201608677] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 11/07/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Yusuke Kimura
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Toru Komatsu
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Precursory Research for Embryonic Science and Technology, PRESTO, Japan, Science and Technology Agency, JST; 4-1-8 Honcho Kawaguchi Saitama 332-0012 Japan
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1, Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Kouichi Yanagi
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Kenjiro Hanaoka
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Tasuku Ueno
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Takuya Terai
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Hirotatsu Kojima
- Discovery Initiative (DDI); The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Takayoshi Okabe
- Discovery Initiative (DDI); The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Tetsuo Nagano
- Discovery Initiative (DDI); The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Yasuteru Urano
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Graduate School of Medicine; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Core Research for Evolutional Science and Technology, CREST, Investigator, Japan, Agency for Medical Research and Development, AMED; 1-7-1 Otemachi Chiyoda-ku Tokyo 100-0004 Japan
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1, Hongo Bunkyo-ku Tokyo 113-0033 Japan
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4
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Kimura Y, Komatsu T, Yanagi K, Hanaoka K, Ueno T, Terai T, Kojima H, Okabe T, Nagano T, Urano Y. Development of Chemical Tools to Monitor and Control Isoaspartyl Peptide Methyltransferase Activity. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201608677] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Yusuke Kimura
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Toru Komatsu
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Precursory Research for Embryonic Science and Technology, PRESTO, Japan, Science and Technology Agency, JST 4-1-8 Honcho Kawaguchi Saitama 332-0012 Japan
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1, Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Kouichi Yanagi
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Kenjiro Hanaoka
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Tasuku Ueno
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Takuya Terai
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Hirotatsu Kojima
- Discovery Initiative (DDI) The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Takayoshi Okabe
- Discovery Initiative (DDI) The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Tetsuo Nagano
- Discovery Initiative (DDI) The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Yasuteru Urano
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Graduate School of Medicine The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Core Research for Evolutional Science and Technology, CREST, Investigator, Japan, Agency for Medical Research and Development, AMED 1-7-1 Otemachi Chiyoda-ku Tokyo 100-0004 Japan
- Graduate School of Pharmaceutical Sciences The University of Tokyo 7-3-1, Hongo Bunkyo-ku Tokyo 113-0033 Japan
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Banerjee S, Dutta T, Lahiri S, Sengupta S, Gangopadhyay A, Kumar Karri S, Chakraborty S, Bhattacharya D, Ghosh AK. Enzymatic attributes of an l-isoaspartyl methyltransferase from Candida utilis and its role in cell survival. Biochem Biophys Rep 2015; 4:59-75. [PMID: 29124188 PMCID: PMC5668901 DOI: 10.1016/j.bbrep.2015.08.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 08/23/2015] [Accepted: 08/24/2015] [Indexed: 12/17/2022] Open
Abstract
BACKGROUNDS Spontaneous deamidation and isoaspartate (IsoAsp) formation contributes to aging and reduced longevity in cells. A protein-l-isoaspartate (d-aspartate) O-methyltransferase (PCMT) is responsible for minimizing IsoAsp moieties in most organisms. METHODS PCMT was purified in its native form from yeast Candida utilis. The role of the native PCMT in cell survival and protein repair was investigated by manipulating intracellular PCMT levels with Oxidized Adenosine (AdOx) and Lithium Chloride (LiCl). Proteomic Identification of possible cellular targets was carried out using 2-dimensional gel electrophoresis, followed by on-Blot methylation and mass spectrometric analysis. RESULTS The 25.4 kDa native PCMT from C. utilis was found to have a Km of 3.5 µM for AdoMet and 33.36 µM for IsoAsp containing Delta Sleep Inducing Peptide (DSIP) at pH 7.0. Native PCMT comprises of 232 amino acids which is coded by a 698 bp long nucleotide sequence. Phylogenetic comparison revealed the PCMT to be related more closely with the prokaryotic homologs. Increase in PCMT levels in vivo correlated with increased cell survival under physiological stresses. PCMT expression was seen to be linked with increased intracellular reactive oxygen species (ROS) concentration. Proteomic identification of possible cellular substrates revealed that PCMT interacts with proteins mainly involved with cellular housekeeping. PCMT effected both functional and structural repair in aged proteins in vitro. GENERAL SIGNIFICANCE Identification of PCMT in unicellular eukaryotes like C. utilis promises to make investigations into its control machinery easier owing to the familiarity and flexibility of the system.
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Affiliation(s)
- Shakri Banerjee
- Drug Development, Diagnostics and Biotechnology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
| | - Trina Dutta
- Drug Development, Diagnostics and Biotechnology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
| | - Sagar Lahiri
- Drug Development, Diagnostics and Biotechnology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
| | - Shinjinee Sengupta
- Drug Development, Diagnostics and Biotechnology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
| | - Anushila Gangopadhyay
- Drug Development, Diagnostics and Biotechnology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
| | - Suresh Kumar Karri
- Infectious Diseases and Immunology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
| | - Sandeep Chakraborty
- Infectious Diseases and Immunology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
| | - Debasish Bhattacharya
- Structural Biology and Bioinformatics Division, CSIR- Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
| | - Anil K. Ghosh
- Drug Development, Diagnostics and Biotechnology Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700032, India
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Gallart-Palau X, Serra A, Qian J, Chen CP, Kalaria RN, Sze SK. Temporal lobe proteins implicated in synaptic failure exhibit differential expression and deamidation in vascular dementia. Neurochem Int 2014; 80:87-98. [PMID: 25497727 DOI: 10.1016/j.neuint.2014.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 11/26/2014] [Accepted: 12/02/2014] [Indexed: 12/20/2022]
Abstract
Progressive synaptic failure precedes the loss of neurons and decline in cognitive function in neurodegenerative disorders, but the specific proteins and posttranslational modifications that promote synaptic failure in vascular dementia (VaD) remain largely unknown. We therefore used an isobaric tag for relative and absolute proteomic quantitation (iTRAQ) to profile the synapse-associated proteome of post-mortem human cortex from vascular dementia patients and age-matched controls. Brain tissue from VaD patients exhibited significant down-regulation of critical synaptic proteins including clathrin (0.29; p < 1.0⋅10(-3)) and GDI1 (0.51; p = 3.0⋅10(-3)), whereas SNAP25 (1.6; p = 5.5⋅10(-3)), bassoon (1.4; p = 1.3⋅10(-3)), excitatory amino acid transporter 2 (2.6; p = 9.2⋅10(-3)) and Ca(2+)/calmodulin dependent kinase II (1.6; p = 3.0⋅10(-2)) were substantially up-regulated. Our analyses further revealed divergent patterns of protein modification in the dementia patient samples, including a specific deamidation of synapsin1 predicted to compromise protein structure. Our results reveal potential molecular targets for intervention in synaptic failure and prevention of cognitive decline in VaD.
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Affiliation(s)
| | - Aida Serra
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Jingru Qian
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Christopher P Chen
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Memory, Aging and Cognition Centre, National University Health System, Singapore
| | - Raj N Kalaria
- Institute for Ageing and Health, NIHR Biomedical Research Building, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, United Kingdom
| | - Siu Kwan Sze
- School of Biological Sciences, Nanyang Technological University, Singapore.
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7
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Vigneswara V, Cass S, Wayne D, Bolt EL, Ray DE, Carter WG. Molecular ageing of alpha- and Beta-synucleins: protein damage and repair mechanisms. PLoS One 2013; 8:e61442. [PMID: 23630590 PMCID: PMC3632608 DOI: 10.1371/journal.pone.0061442] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 03/14/2013] [Indexed: 11/19/2022] Open
Abstract
Abnormal α-synuclein aggregates are hallmarks of a number of neurodegenerative diseases. Alpha synuclein and β-synucleins are susceptible to post-translational modification as isoaspartate protein damage, which is regulated in vivo by the action of the repair enzyme protein L-isoaspartyl O-methyltransferase (PIMT). We aged in vitro native α-synuclein, the α-synuclein familial mutants A30P and A53T that give rise to Parkinsonian phenotypes, and β-synuclein, at physiological pH and temperature for a time course of up to 20 days. Resolution of native α-synuclein and β-synuclein by two dimensional techniques showed the accumulation of a number of post-translationally modified forms of both proteins. The levels of isoaspartate formed over the 20 day time course were quantified by exogenous methylation with PIMT using S-Adenosyl-L-[3H-methyl]methionine as a methyl donor, and liquid scintillation counting of liberated 3H-methanol. All α-synuclein proteins accumulated isoaspartate at ∼1% of molecules/day, ∼20 times faster than for β-synuclein. This disparity between rates of isoaspartate was confirmed by exogenous methylation of synucleins by PIMT, protein resolution by one-dimensional denaturing gel electrophoresis, and visualisation of 3H-methyl esters by autoradiography. Protein silver staining and autoradiography also revealed that α-synucleins accumulated stable oligomers that were resistant to denaturing conditions, and which also contained isoaspartate. Co-incubation of approximately equimolar β-synuclein with α-synuclein resulted in a significant reduction of isoaspartate formed in all α-synucleins after 20 days of ageing. Co-incubated α- and β-synucleins, or α, or β synucleins alone, were resolved by non-denaturing size exclusion chromatography and all formed oligomers of ∼57.5 kDa; consistent with tetramerization. Direct association of α-synuclein with β-synuclein in column fractions or from in vitro ageing co-incubations was demonstrated by their co-immunoprecipitation. These results provide an insight into the molecular differences between α- and β-synucleins during ageing, and highlight the susceptibility of α-synuclein to protein damage, and the potential protective role of β-synuclein.
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Affiliation(s)
- Vasanthy Vigneswara
- School of Biomedical Sciences, The University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Simon Cass
- School of Biomedical Sciences, The University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Declan Wayne
- School of Graduate Entry Medicine and Health, University of Nottingham Medical School, Royal Derby Hospital, Derby, United Kingdom
| | - Edward L. Bolt
- School of Biomedical Sciences, The University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - David E. Ray
- School of Biomedical Sciences, The University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Wayne G. Carter
- School of Graduate Entry Medicine and Health, University of Nottingham Medical School, Royal Derby Hospital, Derby, United Kingdom
- * E-mail:
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8
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New proteomic developments to analyze protein isomerization and their biological significance in plants. J Proteomics 2011; 74:1475-82. [DOI: 10.1016/j.jprot.2011.04.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 04/01/2011] [Accepted: 04/28/2011] [Indexed: 11/30/2022]
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Furuchi T, Sakurako K, Katane M, Sekine M, Homma H. The role of protein L-isoaspartyl/D-aspartyl O-methyltransferase (PIMT) in intracellular signal transduction. Chem Biodivers 2010; 7:1337-48. [PMID: 20564550 DOI: 10.1002/cbdv.200900273] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Under physiological conditions, L-aspartyl (L-Asp) and L-asparaginyl residues in proteins are spontaneously isomerized or racemized to D-aspartyl (D-Asp) or D,L-isoaspartyl (D,L-isoAsp) residue. These atypical Asp residues can interfere with protein activity and lead to disruption of cellular function. Protein L-isoaspartyl/D-aspartyl O-methyltransferase (PIMT) is a repair enzyme that initiates the conversion of L-isoAsp (or D-Asp) residues to L-Asp residues. PIMT-Deficient mice exhibit accumulation of L-isoAsp in several tissues and die from progressive epileptic seizures at a mean age of 42 days. However, the biological roles of PIMT are still largely unknown. To further our understanding of the function of this protein, we developed an assay to measure PIMT activity in cell lysates. Additionally, we generated PIMT-knockdown cells by stable transfection of HEK293 cells with PIMT small interfering (si) RNA. Northern blotting and immunoblot analysis revealed that PIMT mRNA and protein levels were significantly decreased in the knockdown cells. In addition, significant levels of proteins that contained isoAsp residues accumulated in these cells, and immunoblot analysis revealed that Raf-1, MEK, and ERK were hyperphosphorylated upon EGF stimulation compared to control cells. These results indicate that the ability to repair atypical Asp residues is important for normal MAP kinase signaling.
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Affiliation(s)
- Takemitsu Furuchi
- Laboratory of Biomolecular Science, Department of Pharmaceutical Life Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
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Yang H, Zubarev RA. Mass spectrometric analysis of asparagine deamidation and aspartate isomerization in polypeptides. Electrophoresis 2010; 31:1764-72. [PMID: 20446295 PMCID: PMC3104603 DOI: 10.1002/elps.201000027] [Citation(s) in RCA: 131] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
One of the most frequent modifications in proteins and peptides is the deamidation of asparagine, a spontaneous non-enzymatic reaction leading to a mixture of L,D-succinimidyl, L,D-aspartyl, and L,D-isoaspartyl forms, with L-isoaspartyl dominating. Spontaneous isomerization of L-Asp yields the same products. In vivo, these unusual forms of aspartate are repaired by the protein L-isoaspartyl O-methyltransferase enzyme, with the balance between isomerization and repair affecting the organism physiology. Mass spectrometric analysis of this balance involves isomer separation, iso-Asp/Asp quantification, and iso-Asp site identification. This review highlights the issues associated with these steps and discusses the prospects of high-throughput iso-Asp analysis.
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Affiliation(s)
- Hongqian Yang
- Division of Molecular Biometry, Department of Medicinal Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
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11
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Banfield KL, Gomez TA, Lee W, Clarke S, Larsen PL. Protein-repair and hormone-signaling pathways specify dauer and adult longevity and dauer development in Caenorhabditis elegans. J Gerontol A Biol Sci Med Sci 2008; 63:798-808. [PMID: 18772467 DOI: 10.1093/gerona/63.8.798] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Protein damage that accumulates during aging can be mitigated by a repair methyltransferase, the l-isoaspartyl-O-methyltransferase. In Caenorhabditis elegans, the pcm-1 gene encodes this enzyme. In response to pheromone, we show that pcm-1 mutants form fewer dauer larvae with reduced survival due to loss of the methyltransferase activity. Mutations in daf-2, an insulin/insulin-like growth factor-1-like receptor, and daf-7, a transforming growth factor-beta-like ligand, modulate pcm-1 dauer defects. Additionally, daf-2 and daf-7 mutant dauer larvae live significantly longer than wild type. Although dauer larvae are resistant to many environmental stressors, a proportionately larger decrease in dauer larvae life spans occurred at 25 degrees C compared to 20 degrees C than in adult life span. At 25 degrees C, mutation of the daf-7 or pcm-1 genes does not change adult life span, whereas mutation of the daf-2 gene and overexpression of PCM-1 increases adult life span. Thus, there are both overlapping and distinct mechanisms that specify dauer and adult longevity.
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Affiliation(s)
- Kelley L Banfield
- Department of Cellular and Structural Biology, University of Texas Science Center at San Antonio, San Antonio, TX 78229, USA
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12
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Kosugi S, Furuchi T, Katane M, Sekine M, Shirasawa T, Homma H. Suppression of protein l-isoaspartyl (d-aspartyl) methyltransferase results in hyperactivation of EGF-stimulated MEK-ERK signaling in cultured mammalian cells. Biochem Biophys Res Commun 2008; 371:22-7. [DOI: 10.1016/j.bbrc.2008.03.109] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2008] [Accepted: 03/23/2008] [Indexed: 12/26/2022]
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13
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Chapter 16 Analysis of Deamidation in Proteins. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s0166-526x(08)00216-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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14
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Vigneswara V, Lowenson JD, Powell CD, Thakur M, Bailey K, Clarke S, Ray DE, Carter WG. Proteomic Identification of Novel Substrates of a Protein Isoaspartyl Methyltransferase Repair Enzyme. J Biol Chem 2006; 281:32619-29. [PMID: 16923807 DOI: 10.1074/jbc.m605421200] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report the use of a proteomic strategy to identify hitherto unknown substrates for mammalian protein l-isoaspartate O-methyltransferase. This methyltransferase initiates the repair of isoaspartyl residues in aged or stress-damaged proteins in vivo. Tissues from mice lacking the methyltransferase (Pcmt1(-/-)) accumulate more isoaspartyl residues than their wild-type littermates, with the most "damaged" residues arising in the brain. To identify the proteins containing these residues, brain homogenates from Pcmt1(-/-) mice were methylated by exogenous repair enzyme and the radiolabeled methyl donor S-adenosyl-[methyl-(3)H]methionine. Methylated proteins in the homogenates were resolved by both one-dimensional and two-dimensional electrophoresis, and methyltransferase substrates were identified by their increased radiolabeling when isolated from Pcmt1(-/-) animals compared with Pcmt1(+/+) littermates. Mass spectrometric analyses of these isolated brain proteins reveal for the first time that microtubule-associated protein-2, calreticulin, clathrin light chains a and b, ubiquitin carboxyl-terminal hydrolase L1, phosphatidylethanolamine-binding protein, stathmin, beta-synuclein, and alpha-synuclein, are all substrates for the l-isoaspartate methyltransferase in vivo. Our methodology for methyltransferase substrate identification was further supplemented by demonstrating that one of these methyltransferase targets, microtubule-associated protein-2, could be radiolabeled within Pcmt1(-/-) brain extracts using radioactive methyl donor and exogenous methyltransferase enzyme and then specifically immunoprecipitated with microtubule-associated protein-2 antibodies to recover co-localized protein with radioactivity. We comment on the functional significance of accumulation of relatively high levels of isoaspartate within these methyltransferase targets in the context of the histological and phenotypical changes associated with the methyltransferase knock-out mice.
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Affiliation(s)
- Vasanthy Vigneswara
- Medical Research Council Applied Neuroscience Group, School of Biomedical Sciences, The University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, United Kingdom
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15
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Zhu JX, Doyle HA, Mamula MJ, Aswad DW. Protein repair in the brain, proteomic analysis of endogenous substrates for protein L-isoaspartyl methyltransferase in mouse brain. J Biol Chem 2006; 281:33802-13. [PMID: 16959769 DOI: 10.1074/jbc.m606958200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein L-isoaspartyl methyltransferase (PIMT) catalyzes repair of L-isoaspartyl peptide bonds, a major source of protein damage under physiological conditions. PIMT knock-out (KO) mice exhibit brain enlargement and fatal epileptic seizures. All organs accumulate isoaspartyl proteins, but only the brain manifests an overt pathology. To further explore the role of PIMT in brain function, we undertook a global analysis of endogenous substrates for PIMT in mouse brain. Extracts from PIMT-KO mice were subjected to two-dimensional gel electrophoresis and blotted onto membranes. Isoaspartyl proteins were radiolabeled on-blot using [methyl-(3)H]S-adenosyl-L-methionine and recombinant PIMT. Fluorography of the blot revealed 30-35 (3)H-labeled proteins, 22 of which were identified by peptide mass fingerprinting. These isoaspartate-prone proteins represent a wide range of cellular functions, including neuronal development, synaptic transmission, cytoskeletal structure and dynamics, energy metabolism, nitrogen metabolism, pH homeostasis, and protein folding. The following five proteins, all of which are rich in neurons, accumulated exceptional levels of isoaspartate: collapsin response mediator protein 2 (CRMP2/ULIP2/DRP-2), dynamin 1, synapsin I, synapsin II, and tubulin. Several of the proteins identified here are prone to age-dependent oxidation in vivo, and many have been identified as autoimmune antigens, of particular interest because isoaspartate can greatly enhance the antigenicity of self-peptides. We propose that the PIMT-KO phenotype results from the cumulative effect of isoaspartate-related damage to a number of the neuron-rich proteins detected in this study. Further study of the isoaspartate-prone proteins identified here may help elucidate the molecular basis of one or more developmental and/or age-related neurological diseases.
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Affiliation(s)
- Jeff X Zhu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697, USA
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16
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Nojiri H, Shimizu T, Funakoshi M, Yamaguchi O, Zhou H, Kawakami S, Ohta Y, Sami M, Tachibana T, Ishikawa H, Kurosawa H, Kahn RC, Otsu K, Shirasawa T. Oxidative stress causes heart failure with impaired mitochondrial respiration. J Biol Chem 2006; 281:33789-801. [PMID: 16959785 DOI: 10.1074/jbc.m602118200] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Elderly people insidiously manifest the symptoms of heart failure, such as dyspnea and/or physical disabilities in an age-dependent manner. Although previous studies suggested that oxidative stress plays a pathological role in the development of heart failure, no direct evidence has been documented so far. In order to investigate the pathological significance of oxidative stress in the heart, we generated heart/muscle-specific manganese superoxide dismutase-deficient mice. The mutant mice developed progressive congestive heart failure with specific molecular defects in mitochondrial respiration. In this paper, we showed for the first time that the oxidative stress caused specific morphological changes of mitochondria, excess formation of superoxide (O(2)(*)(-)), reduction of ATP, and transcriptional alterations of genes associated with heart failure in respect to cardiac contractility. Accordingly, administration of a superoxide dismutase mimetic significantly ameliorated the symptoms. These results implied that O(2)(*)(-) generated in mitochondria played a pivotal role in the development and progression of heart failure. We here present a bona fide model for human cardiac failure with oxidative stress valuable for therapeutic interventions.
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Affiliation(s)
- Hidetoshi Nojiri
- Research Team for Molecular Biomarkers, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo 173-0015, Japan
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17
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Reissner KJ, Paranandi MV, Luc TM, Doyle HA, Mamula MJ, Lowenson JD, Aswad DW. Synapsin I is a major endogenous substrate for protein L-isoaspartyl methyltransferase in mammalian brain. J Biol Chem 2006; 281:8389-98. [PMID: 16443604 DOI: 10.1074/jbc.m510716200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The accumulation of potentially deleterious L-isoaspartyl linkages in proteins is prevented by the action of protein L-isoaspartyl O-methyltransferase, a widely distributed enzyme that is particularly active in mammalian brain. Methyltransferase-deficient (knock-out) mice exhibit greatly increased levels of isoaspartate and typically succumb to fatal epileptic seizures at 4-10 weeks of age. The link between isoaspartate accumulation and the neurological abnormalities of these mice is poorly understood. Here, we demonstrate that synapsin I from knock-out mice contains 0.9 +/- 0.3 mol of isoaspartate/mol of synapsin, whereas the levels in wild-type and heterozygous mice are undetectable. Transgenic mice that selectively express methyltransferase only in neurons show reduced levels of synapsin damage, and the degree of reduction correlates with the phenotype of these mice. Isoaspartate levels in synapsin from the knock-out mice are five to seven times greater than those in the average protein from brain cytosol or from a synaptic vesicle-enriched fraction. The isoaspartyl sites in synapsin from knock-out mice are efficiently repaired in vitro by incubation with purified methyltransferase and S-adenosyl-L-methionine. These findings demonstrate that synapsin I is a major substrate for the isoaspartyl methyltransferase in neurons and suggest that isoaspartate-related alterations in the function of presynaptic proteins may contribute to the neurological abnormalities of mice deficient in this enzyme.
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Affiliation(s)
- Kathryn J Reissner
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, USA
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18
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O'Connor CM. 13 Protein L-isoaspartyl, D-aspartyl O-methyltransferases: Catalysts for protein repair. Enzymes 2006; 24:385-433. [PMID: 26718047 DOI: 10.1016/s1874-6047(06)80015-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023]
Abstract
Protein L-isoaspartyl, D-aspartyl O-methyltransferases (PIMTs) are ancient enzymes distributed through all phylogenetic domains. PIMTs catalyze the methylation of L-isoaspartyl, and to a lesser extent D-aspartyl, residues arising from the spontaneous deamidation and isomerization of protein asparaginyl and aspartyl residues. PIMTs catalyze the methylation of isoaspartyl residues in a large number of primary sequence configurations, which accounts for the broad specificity of the enzyme for protein substrates both in vitro and in vivo. PIMT-catalyzed methylation of isoaspartyl substrates initiates the repair of the polypeptide backbone in its damaged substrates by a spontaneous mechanism that involves a succinimidyl intermediate. The repair process catalyzed by PEVITs is not completely efficient, however, leaving open the possibility that unidentified enzymatic activities cooperate with PIMT in the repair process. Structurally, PIMTs are members of the class I family of AdoMet-dependent methyltransferases. PIMTs have a unique topological arrangement of strands in the central β sheet that provides a signature for this class of enzymes. The regulation and physiological significance of PIMT has been studied in several model organisms. PIMTs are constitutively synthesized by cells, but they can be upregulated in response to conditions that are potentially damaging to protein structures, or when proteins are stored for prolonged periods of time. Disruption of PIMT genes in bacteria and simple eukaryotes produces subtle phenotypes that are apparent only under stress. Loss of PIMT function in transgenic mice leads to fatalepilepsy, suggesting that PIMT function is particularly important to neurons in mammals.
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Affiliation(s)
- Clare M O'Connor
- Biology Department Boston College 140 Commonwealth Avenue Chestnut Hill, MA 02467, USA
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Shimizu T, Matsuoka Y, Shirasawa T. Biological significance of isoaspartate and its repair system. Biol Pharm Bull 2005; 28:1590-6. [PMID: 16141521 DOI: 10.1248/bpb.28.1590] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Isomerization of L-aspartate and deamidation of L-asparagine in proteins or peptides dominantly give rise to L-isoaspartate by a non-enzymatic reaction via succinimide as a intermediate under physiological conditions. Isoaspartates have been identified in a variety of cellular proteins in vivo as well as pathologically deposited proteins in neurodegenerative brain tissue. We described here that the formation of isoaspartate is enhanced in amyloid-beta (Abeta) peptides in Alzheimer's disease (AD). Specific antibodies recognizing isoaspartate of Abeta revealed that isomerized Abeta peptides were deposited in senile plaques as well as amyloid-bearing vessels. Moreover, it was revealed that Abeta peptides, isomerized at position 7 or 23, were differentially deposited in senile plaques and vascular amyloids in AD brains. In vitro experiments showed that the modification at position 23 greatly enhanced the aggregation of Abeta. Furthermore, systematic proline substitution analyses revealed that the beta-turn structure at positions 22 and 23 of Abeta42 plays a crucial role in the aggregation and neurotoxicity of Abeta peptides. It is suggested that spontaneous isomerization at position 23 induces the conformational change to form a beta-turn at position 23, which plays a pathogenic role in the deposition of Abeta peptides in sporadic AD. Protein L-isoaspartyl methyltransferase (PIMT) is a putative protein repair enzyme, which converts L-isoaspartyl residues in damaged proteins to normal L-aspartyl residues. PIMT-deficient mice manifested neurodegenerative changes concomitant with the accumulation of L-isoaspartate in the brain. We discuss here the pathological implications of the formation of isoaspartate in damaged proteins during neurodegeneration in model mice and AD.
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Affiliation(s)
- Takahiko Shimizu
- Research Team for Molecular Biomarkers, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
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20
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Lapointe M, Lanthier J, Moumdjian R, Régina A, Desrosiers RR. Expression and activity of l-isoaspartyl methyltransferase decrease in stage progression of human astrocytic tumors. ACTA ACUST UNITED AC 2005; 135:93-103. [PMID: 15857672 DOI: 10.1016/j.molbrainres.2004.12.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Revised: 09/03/2004] [Accepted: 12/05/2004] [Indexed: 11/30/2022]
Abstract
Protein l-isoaspartyl methyltransferase (PIMT) functions as a repair enzyme that acts upon damaged proteins bearing abnormal aspartyl residues. We previously reported that PIMT expression and activity are reduced by half in human epileptic hippocampus. Here we investigated PIMT regulation in astrocytic tumors, which are the most common human brain tumors. PIMT expression and enzyme activity were significantly decreased in all grades of human astrocytic tumors. More precisely, PIMT levels were significantly lower by 76% in pilocytic astrocytomas (grade I), 46% in astrocytomas (grade II), 69% in anaplastic astrocytomas (grade III), and a marked 80% in glioblastomas (grade IV) as compared to normal brains. RT-PCR analysis showed that levels of type I PIMT mRNA were up-regulated while those of type II PIMT mRNA were down-regulated in glioblastomas. Furthermore, the reduced PIMT levels correlated closely with a decrease in the number of neuron cells in astrocytic tumors as assessed by measuring the neuron-specific enolase level. Many proteins with abnormal aspartyl residues accumulated in brain tumors and some were specific to individual grades of astrocytic tumors. Similar results were obtained, either by measuring the reduction in PIMT activity and expression or by measuring the formation of abnormal proteins, in an orthotopic rat brain tumor model implanted with invasive CNS-1 glioma cells. The novelty of these findings was to provide the first evidence for a marked reduction of PIMT expression and activity during stage progression of astrocytic tumors in humans.
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Affiliation(s)
- Marjolaine Lapointe
- Université du Québec à Montréal, C.P. 8888, Succursale Centre-Ville, Montréal, Québec, Canada
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Vitali R, Clarke S. Improved rotorod performance and hyperactivity in mice deficient in a protein repair methyltransferase. Behav Brain Res 2004; 153:129-41. [PMID: 15219714 DOI: 10.1016/j.bbr.2003.11.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2003] [Revised: 11/17/2003] [Accepted: 11/17/2003] [Indexed: 11/18/2022]
Abstract
The protein L-isoaspartate (D-aspartate)-O-methyltransferase participates in the repair of age-induced protein damage by initiating the conversion of abnormal aspartyl residues within proteins to normal L-aspartyl residues. Previous studies have shown that mice deficient in the gene encoding this enzyme (Pcmt1-/-) accumulate damaged proteins, have altered levels of brain S-adenosylmethionine (AdoMet) and S-adenosylhomocysteine (AdoHcy), and suffer from epileptic seizures that result in death at an average age of about 42 days. In this study, we found that the behavior of Pcmt1-/- mice is abnormal in comparison to their wild-type (Pcmt1+/+) and heterozygous (Pcmt1+/-) littermates in two standard quantitative behavioral assays - the accelerating rotorod and the open-field test. On the accelerating rotorod, we found Pcmt1-/- mice actually perform significantly better than their heterozygous and wild-type littermates, a situation that has only been infrequently described in the literature and has not been described to date for epilepsy-prone mice. The Pcmt1-/- mice show, however, hyperactivity in the open-field test that becomes more pronounced with age, with a partial habituation with time in the chamber. Additionally, these mice demonstrate a strong thigmotaxic movement pattern. We present evidence that these phenotypes are not related to the alterations of the AdoMet/AdoHcy ratio in the brain and thus may be a function of the accumulation of damaged proteins. These results implicate a role for this enzyme in motor coordination and cerebellum development and suggest the importance of the function of the repair methyltransferase in hippocampal-dependent spatial learning.
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Affiliation(s)
- Ryan Vitali
- Department of Chemistry and Biochemistry, Molecular Biology Institute, UCLA, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569, USA
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Rubens DD. Are lethal audiogenic seizures a missing link to the sudden infant death syndrome? Med Hypotheses 2004; 63:87-91. [PMID: 15193355 DOI: 10.1016/j.mehy.2004.02.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Accepted: 02/02/2004] [Indexed: 11/22/2022]
Abstract
The pathogenesis of human seizure disorders has largely been derived from rodent models. A number of rodent and chick strains exhibit a genetic predisposition for lethal audiogenic seizures (AGSs) in the first year of life. Consideration is warranted that this disorder may be linked to the sudden infant death syndrome (SIDS). Factors that carry a strong association with SIDS such as hyperthermia and the prone sleeping position would conceivably play a significant role in a human AGS syndrome. Importantly, there is data to support the likelihood that motor seizure activity may be absent in infants with an AGS syndrome. Rodent AGSs may hold important clues to unraveling the mystery of SIDS.
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Affiliation(s)
- Daniel D Rubens
- Department of Anesthesia and Critical Care, Children's Hospital and Regional Medical Center, University of Washington, School of Medicine, 4800 Sand Point Way NE, Seattle, WA 98105, USA.
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