1
|
Nai G, Liang G, Ma W, Lu S, Li Y, Gou H, Guo L, Chen B, Mao J. Overexpression VaPYL9 improves cold tolerance in tomato by regulating key genes in hormone signaling and antioxidant enzyme. BMC PLANT BIOLOGY 2022; 22:344. [PMID: 35840891 PMCID: PMC9284830 DOI: 10.1186/s12870-022-03704-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 06/17/2022] [Indexed: 06/02/2023]
Abstract
BACKGROUND Abscisic acid (ABA) has been reported in controlling plant growth and development, and particularly dominates a role in resistance to abiotic stress. The Pyrabactin Resistance1/PYR1-Like /Regulatory Components of ABA receptors (PYR1/PYL/RCAR) gene family, of which the PYL9 is a positive regulator related to stress response in ABA signaling transduction. Although the family has been identified in grape, detailed VaPYL9 function in cold stress remains unknown. RESULTS In order to explore the cold tolerance mechanism in grape, VaPYL9 was cloned from Vitis amurensis. The subcellular localization showed that VaPYL9 was mainly expressed in the plasma membrane. Yeast two-hybrid (Y2H) showed VaPCMT might be a potential interaction protein of VaPYL9. Through the overexpression of VaPYL9 in tomatoes, results indicated transgenic plants had higher antioxidant enzyme activities and proline content, lower malondialdehyde (MDA) and H2O2 content, and improving the ability to scavenge reactive oxygen species than wild-type (WT). Additionally, ABA content and the ratio of ABA/IAA kept a higher level than WT. Quantitative real-time PCR (qRT-PCR) showed that VaPYL9, SlNCED3, SlABI5, and antioxidant enzyme genes (POD, SOD, CAT) were up-regulated in transgenic tomatoes. Transcriptome sequencing (RNA-seq) found that VaPYL9 overexpression caused the upregulation of key genes PYR/PYL, PYL4, MAPK17/18, and WRKY in transgenic tomatoes under cold stress. CONCLUSION Overexpression VaPYL9 enhances cold resistance of transgenic tomatoes mediated by improving antioxidant enzymes activity, reducing membrane damages, and regulating key genes in plant hormones signaling and antioxidant enzymes.
Collapse
Affiliation(s)
- Guojie Nai
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China
| | - Guoping Liang
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China
| | - Weifeng Ma
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China
| | - Shixiong Lu
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China
| | - Yanmei Li
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China
| | - Huimin Gou
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China
| | - Lili Guo
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China
| | - Baihong Chen
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China
| | - Juan Mao
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China.
| |
Collapse
|
2
|
Soliman R, Cordero-Maldonado ML, Martins TG, Moein M, Conrotte JF, Warmack RA, Skupin A, Crawford AD, Clarke SG, Linster CL. l-Isoaspartyl Methyltransferase Deficiency in Zebrafish Leads to Impaired Calcium Signaling in the Brain. Front Genet 2021; 11:612343. [PMID: 33552132 PMCID: PMC7859441 DOI: 10.3389/fgene.2020.612343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/21/2020] [Indexed: 11/13/2022] Open
Abstract
Isomerization of l-aspartyl and l-asparaginyl residues to l-isoaspartyl residues is one type of protein damage that can occur under physiological conditions and leads to conformational changes, loss of function, and enhanced protein degradation. Protein l-isoaspartyl methyltransferase (PCMT) is a repair enzyme whose action initiates the reconversion of abnormal l-isoaspartyl residues to normal l-aspartyl residues in proteins. Many lines of evidence support a crucial role for PCMT in the brain, but the mechanisms involved remain poorly understood. Here, we investigated PCMT activity and function in zebrafish, a vertebrate model that is particularly well-suited to analyze brain function using a variety of techniques. We characterized the expression products of the zebrafish PCMT homologous genes pcmt and pcmtl. Both zebrafish proteins showed a robust l-isoaspartyl methyltransferase activity and highest mRNA transcript levels were found in brain and testes. Zebrafish morphant larvae with a knockdown in both the pcmt and pcmtl genes showed pronounced morphological abnormalities, decreased survival, and increased isoaspartyl levels. Interestingly, we identified a profound perturbation of brain calcium homeostasis in these morphants. An abnormal calcium response upon ATP stimulation was also observed in mouse hippocampal HT22 cells knocked out for Pcmt1. This work shows that zebrafish is a promising model to unravel further facets of PCMT function and demonstrates, for the first time in vivo, that PCMT plays a pivotal role in the regulation of calcium fluxes.
Collapse
Affiliation(s)
- Remon Soliman
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | | | - Teresa G Martins
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Mahsa Moein
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Jean-François Conrotte
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Rebeccah A Warmack
- Department of Chemistry and Biochemistry, The Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, United States
| | - Alexander Skupin
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg.,University of California, San Diego, La Jolla, CA, United States
| | - Alexander D Crawford
- Department of Preclinical Sciences and Pathology, Norwegian University of Life Sciences, Oslo, Norway.,Institute for Orphan Drug Discovery, Bremer Innovations- und Technologiezentrum, Bremen, Germany
| | - Steven G Clarke
- Department of Chemistry and Biochemistry, The Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, United States
| | - Carole L Linster
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| |
Collapse
|
3
|
Kumawat M, Singh R, Karuna I, Ahlawat N, Ahlawat S. Salmonella Typhimurium peptidyl-prolyl cis-trans isomerase C (PPIase C) plays a substantial role in protein folding to maintain the protein structure. World J Microbiol Biotechnol 2020; 36:168. [PMID: 33029674 DOI: 10.1007/s11274-020-02943-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 09/29/2020] [Indexed: 01/18/2023]
Abstract
Salmonella is a well-known food-borne pathogen causing disease in humans and animals worldwide. Peptidyl-prolyl isomerases (PPIases) catalyse the cis-trans isomerisation of prolyl bound, which is a slow and rate-limiting step of protein folding. Here, we present the biochemical and molecular characterisation of a novel multi-domain parvulin-type, PPIases-C from the pathogenic bacteria Salmonella Typhimurium, annotated as rPpiC. The recombinant plasmid PpiC_pET28c was used for protein induction using 1.5 mM concentration of isopropyl-β-D-thiogalactopyranoside at 30 °C. Subsequently, the protein was identified by using the LC-MS technique showing high match score and sequence coverage with available PPIases-C proteins database. Using the succinyl-ala-phe-pro-phe-p nitroanilide as a substrate, Vmax of the enzyme was found to be 0.8187 ± 0.1352 µmoles/min and Km = 1.6014 ± 0.8449 µM, respectively. With this, we conclude that rPpiC protein is an active form of protein from Salmonella Typhimurium and plays an important role in protein folding.
Collapse
Affiliation(s)
- Manoj Kumawat
- Department of Microbiology, ICMR- National Institute for Research in Environmental Health, Bhopal, 462030, India. .,Department of Biochemistry & Biochemical Engineering, SHUATS, Allahabad, 211007, India.
| | - Ranu Singh
- Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal, 462066, India
| | - Irungbam Karuna
- Divisions of Biochemistry, Indian Veterinary Research Institute, Izatnagar, India
| | - Neeraj Ahlawat
- Department of Animal Husbandry and Dairying, SHUATS, Allahabad, 211007, India
| | - Sushma Ahlawat
- Department of Biochemistry & Biochemical Engineering, SHUATS, Allahabad, 211007, India.
| |
Collapse
|
4
|
Zhong Y, Hu X, Miao L. Isoflurane preconditioning protects hepatocytes from oxygen glucose deprivation injury by regulating FoxO6. J Biosci 2019; 44:144. [PMID: 31894125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The forkhead protein (FoxO) family plays a crucial role in regulating oxidative stress, cell proliferation, and apoptosis. FoxO6, a member of the FoxO family, helps regulate oxidative stress in gastric cancer and hepatocellular carcinoma. However, it is unclear whether FoxO6 participates in the protective effect of isoflurane preconditioning in liver injury caused by oxidative stress in ischemia. In this study, we explored the role and mechanism of FoxO6 in the protective effect of isoflurane preconditioning during hepatocyte injury caused by oxygen-glucose deprivation (OGD). Cells from the human fetal hepatocyte (LO2) line were incubated with 0%, 1%, 2%, 2.5%, 3%, 3.5%, 4%, or 5% isoflurane for 3 h and then exposed to OGD. Data showed that 3% isoflurane preconditioning inhibited FoxO6 expression, caspase-3 activity, and reactive oxygen species production and promoted cell viability. FoxO6 overexpression abolished the effects of 3% isoflurane preconditioning on caspase-3 activity, reactive oxygen species production, and cell viability in these cells. Moreover, FoxO6 regulated nuclear factor erythroid 2-related factor (Nrf2) expression via c-Myc after 3% isoflurane preconditioning and OGD exposure. Thus, isoflurane preconditioning prevented OGD-induced injury in LO2 cells by modulating FoxO6, c-Myc, and Nrf2 signaling.
Collapse
Affiliation(s)
- Yonghui Zhong
- Department of Anesthesiology, Weinan Central Hospital, Weinan 714000, China
| | | | | |
Collapse
|
5
|
Smiljanic K, Prodic I, Apostolovic D, Cvetkovic A, Veljovic D, Mutic J, van Hage M, Burazer L, Cirkovic Velickovic T. In-depth quantitative profiling of post-translational modifications of Timothy grass pollen allergome in relation to environmental oxidative stress. ENVIRONMENT INTERNATIONAL 2019; 126:644-658. [PMID: 30856452 DOI: 10.1016/j.envint.2019.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 02/02/2019] [Accepted: 03/01/2019] [Indexed: 06/09/2023]
Abstract
An association between pollution (e.g., from traffic emissions) and the increased prevalence of respiratory allergies has been observed. Field-realistic exposure studies provide the most relevant assessment of the effects of the intensity and diversity of urban and industrial contamination on pollen structure and allergenicity. The significance of in-depth post-translational modification (PTM) studies of pollen proteomes, when compared with studies on other aspects of pollution and altered pollen allergenicity, has not yet been determined; hence, little progress has been made within this field. We undertook a comprehensive comparative analysis of multiple polluted and environmentally preserved Phleum pratense (Timothy grass) pollen samples using scanning electron microscopy, in-depth PTM profiling, determination of organic and inorganic pollutants, analysis of the release of sub-pollen particles and phenols/proteins, and analysis of proteome expression using high resolution tandem mass spectrometry. In addition, we used quantitative enzyme-linked immunosorbent assays (ELISA) and immunoglobulin E (IgE) immunoblotting. An increased phenolic content and release of sub-pollen particles was found in pollen samples from the polluted area, including a significantly higher content of mercury, cadmium, and manganese, with irregular long spines on pollen grain surface structures. Antioxidative defense-related enzymes were significantly upregulated and seven oxidative PTMs were significantly increased (methionine, histidine, lysine, and proline oxidation; tyrosine glycosylation, lysine 4-hydroxy-2-nonenal adduct, and lysine carbamylation) in pollen exposed to the chemical plant and road traffic pollution sources. Oxidative modifications affected several Timothy pollen allergens; Phl p 6, in particular, exhibited several different oxidative modifications. The expression of Phl p 6, 12, and 13 allergens were downregulated in polluted pollen, and IgE binding to pollen extract was substantially lower in the 18 patients studied, as measured by quantitative ELISA. Quantitative, unrestricted, and detailed PTM searches using an enrichment-free approach pointed to modification of Timothy pollen allergens and suggested that heavy metals are primarily responsible for oxidative stress effects observed in pollen proteins.
Collapse
Affiliation(s)
- Katarina Smiljanic
- University of Belgrade-Faculty of Chemistry, Centre of Excellence for Molecular Food Sciences and Department of Biochemistry, Belgrade, Serbia.
| | - Ivana Prodic
- Innovation Center Ltd, University of Belgrade-Faculty of Chemistry, Belgrade, Serbia
| | | | - Anka Cvetkovic
- Institute of Public Health of Belgrade, Belgrade, Serbia
| | - Djordje Veljovic
- University of Belgrade-Faculty of Technology and Metallurgy, Belgrade, Serbia
| | - Jelena Mutic
- University of Belgrade-Faculty of Chemistry, Centre of Excellence for Molecular Food Sciences and Department of Biochemistry, Belgrade, Serbia; Ghent University Global Campus, Incheon, South Korea
| | - Marianne van Hage
- Karolinska Institute, Department of Medicine, Solna, Stockholm, Sweden
| | - Lidija Burazer
- Institute of Immunology, Virology and Sera Production, Torlak Institut, Belgrade, Serbia
| | - Tanja Cirkovic Velickovic
- University of Belgrade-Faculty of Chemistry, Centre of Excellence for Molecular Food Sciences and Department of Biochemistry, Belgrade, Serbia; Ghent University Global Campus, Incheon, South Korea; Ghent University, Faculty of Bioscience Engineering, Ghent, Belgium; Serbian Academy of Sciences and Arts, Belgrade, Serbia.
| |
Collapse
|
6
|
Yang ML, Doyle HA, Clarke SG, Herold KC, Mamula MJ. Oxidative Modifications in Tissue Pathology and Autoimmune Disease. Antioxid Redox Signal 2018; 29:1415-1431. [PMID: 29088923 PMCID: PMC6166690 DOI: 10.1089/ars.2017.7382] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SIGNIFICANCE Various autoimmune syndromes are characterized by abnormalities found at the level of tissues and cells, as well as by microenvironmental influences, such as reactive oxygen species (ROS), that alter intracellular metabolism and protein expression. Moreover, the convergence of genetic, epigenetic, and even environmental influences can result in B and T lymphocyte autoimmunity and tissue pathology. Recent Advances: This review describes how oxidative stress to cells and tissues may alter post-translational protein modifications, both directly and indirectly, as well as potentially lead to aberrant gene expression. For example, it has been clearly observed in many systems how oxidative stress directly amplifies carbonyl protein modifications. However, ROS also lead to a number of nonenzymatic spontaneous modifications including deamidation and isoaspartate modification as well as to enzyme-mediated citrullination of self-proteins. ROS have direct effects on DNA methylation, leading to influences in gene expression, chromosome inactivation, and the silencing of genetic elements. Finally, ROS can alter many other cellular pathways, including the initiation of apoptosis and NETosis, triggering the release of modified intracellular autoantigens. CRITICAL ISSUES This review will detail specific post-translational protein modifications, the pathways that control autoimmunity to modified self-proteins, and how products of ROS may be important biomarkers of tissue pathogenesis. FUTURE DIRECTIONS A clear understanding of the many pathways affected by ROS will lead to potential therapeutic manipulations to alter the onset and/or progression of autoimmune disease.
Collapse
Affiliation(s)
- Mei-Ling Yang
- 1 Section of Rheumatology, Yale University School of Medicine , New Haven, Connecticut.,2 Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut
| | - Hester A Doyle
- 1 Section of Rheumatology, Yale University School of Medicine , New Haven, Connecticut.,2 Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut
| | - Steven G Clarke
- 3 Department of Chemistry and Biochemistry, University of California , Los Angeles, Los Angeles, California
| | - Kevan C Herold
- 2 Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut.,4 Department of Immunobiology, Yale University School of Medicine , New Haven, Connecticut
| | - Mark J Mamula
- 1 Section of Rheumatology, Yale University School of Medicine , New Haven, Connecticut.,2 Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut
| |
Collapse
|
7
|
Retraction: Protein Isoaspartate Methyltransferase Prevents Apoptosis Induced by Oxidative Stress in Endothelial Cells: Role of Bcl-Xl Deamidation and Methylation. PLoS One 2018; 13:e0207530. [PMID: 30408107 PMCID: PMC6224115 DOI: 10.1371/journal.pone.0207530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
|
8
|
Beaumatin F, El Dhaybi M, Lasserre JP, Salin B, Moyer MP, Verdier M, Manon S, Priault M. N52 monodeamidated Bcl‑xL shows impaired oncogenic properties in vivo and in vitro. Oncotarget 2017; 7:17129-43. [PMID: 26958941 PMCID: PMC4941376 DOI: 10.18632/oncotarget.7938] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/31/2016] [Indexed: 12/19/2022] Open
Abstract
Bcl-xL is a member of the Bcl-2 family, playing a critical role in the survival of tumor cells. Here, we show that Bcl-xL oncogenic function can be uncoupled from its anti-apoptotic activity when it is regulated by the post-translational deamidation of its Asn52. Bcl-xL activity can be regulated by post-translational modifications: deamidation of Asn52 and 66 into Asp residues was reported to occur exclusively in response to DNA damage, and to cripple its anti-apoptotic activity. Our work reports for the first time the spontaneous occurrence of monodeamidated Asp52Bcl-xL in control conditions, in vivo and in vitro. In the normal and cancer cell lines tested, no less than 30% and up to 56% of Bcl-xL was singly deamidated on Asn52. Functional analyses revealed that singly deamidated Bcl-xL retains anti-apoptotic functions, and exhibits enhanced autophagic activity while harboring impaired clonogenic and tumorigenic properties compared to native Bcl-xL. Additionally, Asp52Bcl-xL remains phosphorylatable, and thus is still an eligible target of anti-neoplasic agents. Altogether our results complement the existing data on Bcl-xL deamidation: they challenge the common acceptance that Asn52 and Asn66 are equally eligible for deamidation, and provide a valuable improvement of our knowledge on the regulation of Bcl-xLoncogenic functions by deamidation.
Collapse
Affiliation(s)
- Florian Beaumatin
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France.,Université Bordeaux Ségalen, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France
| | - Mohamad El Dhaybi
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France.,Université Bordeaux Ségalen, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France.,EA 3842, Homéostasie Cellulaire et Pathologies, Université de Limoges, 87025 Limoges Cedex, France
| | - Jean-Paul Lasserre
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France.,Université Bordeaux Ségalen, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France
| | - Bénédicte Salin
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France.,Université Bordeaux Ségalen, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France
| | | | - Mireille Verdier
- EA 3842, Homéostasie Cellulaire et Pathologies, Université de Limoges, 87025 Limoges Cedex, France
| | - Stéphen Manon
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France.,Université Bordeaux Ségalen, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France
| | - Muriel Priault
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France.,Université Bordeaux Ségalen, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 33077 Bordeaux, France
| |
Collapse
|
9
|
Hao P, Adav SS, Gallart-Palau X, Sze SK. Recent advances in mass spectrometric analysis of protein deamidation. MASS SPECTROMETRY REVIEWS 2017; 36:677-692. [PMID: 26763661 DOI: 10.1002/mas.21491] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 12/28/2015] [Accepted: 12/28/2015] [Indexed: 06/05/2023]
Abstract
Protein deamidation has been proposed to represent a "molecular clock" that progressively disrupts protein structure and function in human degenerative diseases and natural aging. Importantly, this spontaneous process can also modify therapeutic proteins by altering their purity, stability, bioactivity, and antigenicity during drug synthesis and storage. Deamidation occurs non-enzymatically in vivo, but can also take place spontaneously in vitro, hence artificial deamidation during proteomic sample preparation can hamper efforts to identify and quantify endogenous deamidation of complex proteomes. To overcome this, mass spectrometry (MS) can be used to conduct rigorous site-specific characterization of protein deamidation due to the high sensitivity, speed, and specificity offered by this technique. This article reviews recent progress in MS analysis of protein deamidation and discusses the strengths and limitations of common "top-down" and "bottom-up" approaches. Recent advances in sample preparation methods, chromatographic separation, MS technology, and data processing have for the first time enabled the accurate and reliable characterization of protein modifications in complex biological samples, yielding important new data on how deamidation occurs across the entire proteome of human cells and tissues. These technological advances will lead to a better understanding of how deamidation contributes to the pathology of biological aging and major degenerative diseases. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 36:677-692, 2017.
Collapse
Affiliation(s)
- Piliang Hao
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
- Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
| | - Sunil S Adav
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
| | - Xavier Gallart-Palau
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
| | - Siu Kwan Sze
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
| |
Collapse
|
10
|
Liang F, Shi L, Zheng J, Chen S, Wang Y, Zhang J. Neuroprotective Effects of CGP3466B on Apoptosis Are Modulated by Protein-L-isoaspartate (D-aspartate) O-methyltransferase/Mst1 Pathways after Traumatic Brain Injury in Rats. Sci Rep 2017; 7:9201. [PMID: 28835703 PMCID: PMC5569064 DOI: 10.1038/s41598-017-08196-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 07/07/2017] [Indexed: 11/26/2022] Open
Abstract
Neuronal apoptosis chiefly contributes to the cell loss following traumatic brain injury (TBI). CGP3466B is a compound related to the anti-Parkinsonism drug R-(−)-deprenyl. Previous studies have illuminated anti-apoptosis effects of CGP3466B in different cell lines, but the underlying mechanisms have not been fully elucidated. Mammalian sterile 20 (STE20)-like kinase1 (Mst1) is a core component of the Hippo signaling pathway. Protein-L-isoaspartate (D-aspartate) O-methyltransferase (PCMT1) is an enzyme that repairs damaged L-isoaspartyl residues in proteins. The present study was performed to investigate the neuroprotective effects of CGP3466B and to determine a potential PCMT1/Mst1 neuronal anti-apoptotic pathway after TBI. Double immunofluorescence staining demonstrated that PCMT1 and Mst1 are co-located in neurons. Administration of CGP3466B improved neurological function, downregulated the ROS level and alleviated brain edema at 24 h after TBI. CGP3466B alleviates neuronal apoptosis by increasing PCMT1 expression and subsequently inhibiting MST1 activation, resulting in changing the expression levels of Bax, Bcl-2 and active-caspase3. The TUNEL staining results also support the anti-apoptosis effects of CGP3466B. The anti-apoptotic effects of CGP3466B were abolished by chelerythrine, an Mst1 activator, without changing PCMT1 levels. In conclusion, our findings suggest CGP3466B may have a promising therapeutic potential by modulating PCMT1/Mst1 signaling pathway after TBI injury.
Collapse
Affiliation(s)
- Feng Liang
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, China
| | - Ligen Shi
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, China
| | - Jingwei Zheng
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, China
| | - Sheng Chen
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, China
| | - Yangxin Wang
- Department of Orthopaedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, China
| | - Jianmin Zhang
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, China.
| |
Collapse
|
11
|
Beaumatin F, El Dhaybi M, Bobo C, Verdier M, Priault M. Bcl-x L deamidation and cancer: Charting the fame trajectories of legitimate child and hidden siblings. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017. [PMID: 28645514 DOI: 10.1016/j.bbamcr.2017.06.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Bcl-2 family proteins control programmed cell death through a complex network of interactions within and outside of this family, that are modulated by post-translational modifications (PTM). Bcl-xL, an anti-apoptotic member of this family, is overexpressed in a number of cancers, plays an important role in tumorigenesis and is correlated with drug resistance. Bcl-xL is susceptible to a number of different PTMs. Here, we focus on deamidation. We will first provide an overview of protein deamidation. We will then review how the apoptotic and autophagic functions of Bcl-xL are modified by this PTM, and how this impacts on its oncogenic properties. Possible therapeutic outcomes will also be discussed. Finally, we will highlight how the specific case of Bcl-xL deamidation provides groundings to revisit some concepts related to protein deamidation in general.
Collapse
Affiliation(s)
- Florian Beaumatin
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; Université de Bordeaux, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France
| | - Mohamad El Dhaybi
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; Université de Bordeaux, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; EA 3842, Homéostasie Cellulaire et Pathologies, Université de Limoges, 2, rue du Docteur Marcland, 87025 Limoges Cedex, France
| | - Claude Bobo
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; Université de Bordeaux, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France
| | - Mireille Verdier
- EA 3842, Homéostasie Cellulaire et Pathologies, Université de Limoges, 2, rue du Docteur Marcland, 87025 Limoges Cedex, France
| | - Muriel Priault
- CNRS, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France; Université de Bordeaux, Institut de Biochimie et de Génétique Cellulaires, UMR5095, 1 Rue Camille Saint-Saëns, 33077 Bordeaux, France.
| |
Collapse
|
12
|
Shi L, Al-Baadani A, Zhou K, Shao A, Xu S, Chen S, Zhang J. PCMT1 Ameliorates Neuronal Apoptosis by Inhibiting the Activation of MST1 after Subarachnoid Hemorrhage in Rats. Transl Stroke Res 2017; 8:10.1007/s12975-017-0540-8. [PMID: 28534197 DOI: 10.1007/s12975-017-0540-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 05/08/2017] [Accepted: 05/10/2017] [Indexed: 10/19/2022]
Abstract
Mammalian sterile 20-like kinase 1 (MST1) is found to promote neuronal apoptosis. Protein-L-isoaspartate (D-aspartate) O-methyltransferase (PCMT1), an anti-apoptosis factor, was recently identified as an MST1-interacting protein. This study aims to explore the potential role of PCMT1 in reducing MST1-induced neuronal apoptosis after subarachnoid hemorrhage (SAH) in rats. One hundred ninety-eight male Sprague-Dawley rats were used. An exogenous PCMT1 agonist, CGP 3466B, was injected subcutaneously 1 h after the SAH induced by endovascular perforation. Chelerythrine or calyculin A was given immediately via intracerebroventricular administration after SAH. The SAH grade, Garcia score, and brain water content were measured at 24 and 72 h after the SAH. Neuronal apoptosis was detected by an immunofluorescent assay. The expression levels of endogenous PCMT1, MST1, phospho-MST1 (p-MST1), cleaved MST1 (cl-MST1), and apoptosis-related proteins were studied by western blotting. The expression of PCMT1 and MST1 decreased, while the level of active caspase 3 increased in rats after SAH. CGP 3466B treatment improved neurobehavioral function, reduced brain water content, inhibited the activity of MST1, and relieved neuronal apoptosis. These neuroprotective effects were significantly weakened either through accelerating MST1 phosphorylation by calyculin A or increasing cl-MST1 by chelerythrine. PCMT1 inhibited neuronal apoptosis by reducing MST1 phosphorylation and the level of cl-MST1. PCMT1/MST1 pathway might be an alternative therapeutic target for alleviating early brain injury after SAH.
Collapse
Affiliation(s)
- Ligen Shi
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, Zhejiang, 310009, China
| | - Ammar Al-Baadani
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, Zhejiang, 310009, China
| | - Keren Zhou
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, Zhejiang, 310009, China
| | - Anwen Shao
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, Zhejiang, 310009, China
| | - Shenbin Xu
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, Zhejiang, 310009, China
| | - Sheng Chen
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, Zhejiang, 310009, China.
| | - Jianmin Zhang
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, Zhejiang, 310009, China.
- Brain Research Institute, Zhejiang University, Hangzhou, Zhejiang, China.
- Collaborative Innovation Center for Brain Science, Zhejiang University, Hangzhou, Zhejiang, China.
| |
Collapse
|
13
|
Adav SS, Sze SK. Insight of brain degenerative protein modifications in the pathology of neurodegeneration and dementia by proteomic profiling. Mol Brain 2016; 9:92. [PMID: 27809929 PMCID: PMC5094070 DOI: 10.1186/s13041-016-0272-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 10/16/2016] [Indexed: 02/06/2023] Open
Abstract
Dementia is a syndrome associated with a wide range of clinical features including progressive cognitive decline and patient inability to self-care. Due to rapidly increasing prevalence in aging society, dementia now confers a major economic, social, and healthcare burden throughout the world, and has therefore been identified as a public health priority by the World Health Organization. Previous studies have established dementia as a 'proteinopathy' caused by detrimental changes in brain protein structure and function that promote misfolding, aggregation, and deposition as insoluble amyloid plaques. Despite clear evidence that pathological cognitive decline is associated with degenerative protein modifications (DPMs) arising from spontaneous chemical modifications to amino acid side chains, the molecular mechanisms that promote brain DPMs formation remain poorly understood. However, the technical challenges associated with DPM analysis have recently become tractable due to powerful new proteomic techniques that facilitate detailed analysis of brain tissue damage over time. Recent studies have identified that neurodegenerative diseases are associated with the dysregulation of critical repair enzymes, as well as the misfolding, aggregation and accumulation of modified brain proteins. Future studies will further elucidate the mechanisms underlying dementia pathogenesis via the quantitative profiling of the human brain proteome and associated DPMs in distinct phases and subtypes of disease. This review summarizes recent developments in quantitative proteomic technologies, describes how these techniques have been applied to the study of dementia-linked changes in brain protein structure and function, and briefly outlines how these findings might be translated into novel clinical applications for dementia patients. In this review, only spontaneous protein modifications such as deamidation, oxidation, nitration glycation and carbamylation are reviewed and discussed.
Collapse
Affiliation(s)
- Sunil S. Adav
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551 Singapore
| | - Siu Kwan Sze
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551 Singapore
| |
Collapse
|
14
|
Kumawat M, Pesingi PK, Agarwal RK, Goswami TK, Mahawar M. Contribution of protein isoaspartate methyl transferase (PIMT) in the survival of Salmonella Typhimurium under oxidative stress and virulence. Int J Med Microbiol 2016; 306:222-30. [DOI: 10.1016/j.ijmm.2016.04.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 04/07/2016] [Accepted: 04/26/2016] [Indexed: 12/22/2022] Open
|
15
|
Saito H, Yamashita M, Ogasawara M, Yamada N, Niisato M, Tomoyasu M, Deguchi H, Tanita T, Ishida K, Sugai T, Yamauchi K. Chaperone protein l-isoaspartate (d-aspartyl) O-methyltransferase as a novel predictor of poor prognosis in lung adenocarcinoma. Hum Pathol 2016; 50:1-10. [DOI: 10.1016/j.humpath.2015.11.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 11/14/2015] [Accepted: 11/18/2015] [Indexed: 11/27/2022]
|
16
|
Ouanouki A, Desrosiers RR. The enzyme l-isoaspartyl (d-aspartyl) methyltransferase is required for VEGF-dependent endothelial cell migration and tubulogenesis. Mol Cell Biochem 2016; 413:37-46. [DOI: 10.1007/s11010-015-2637-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 12/23/2015] [Indexed: 02/08/2023]
|
17
|
Fares M, Abedi-Valugerdi M, Hassan M, Potácová Z. DNA damage, lysosomal degradation and Bcl-xL deamidation in doxycycline- and minocycline-induced cell death in the K562 leukemic cell line. Biochem Biophys Res Commun 2015; 463:268-74. [DOI: 10.1016/j.bbrc.2015.05.043] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 05/03/2015] [Indexed: 01/21/2023]
|
18
|
Ouazia D, Levros LC, Rassart É, Desrosiers R. The protein l-isoaspartyl (d-aspartyl) methyltransferase protects against dopamine-induced apoptosis in neuroblastoma SH-SY5Y cells. Neuroscience 2015; 295:139-50. [DOI: 10.1016/j.neuroscience.2015.03.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 03/10/2015] [Accepted: 03/14/2015] [Indexed: 11/15/2022]
|
19
|
Xiong XY, Meng S, Yang X, Wang H. Methylation and Atherosclerosis. Atherosclerosis 2015. [DOI: 10.1002/9781118828533.ch32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
20
|
Hess JA, Khasawneh MK. Cancer metabolism and oxidative stress: Insights into carcinogenesis and chemotherapy via the non-dihydrofolate reductase effects of methotrexate. BBA CLINICAL 2015; 3:152-61. [PMID: 26674389 PMCID: PMC4661551 DOI: 10.1016/j.bbacli.2015.01.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 01/08/2015] [Accepted: 01/21/2015] [Indexed: 12/31/2022]
Abstract
Methotrexate has been in use as an anti-cancer agent for over 60 years. Though inhibition of dihydrofolate reductase is its best known mechanisms of action, its non-dihydrofolate reductase dependent mechanisms disrupt metabolic pathways resulting in a depletion of NAD(P)H and increasing oxidative stress. These mechanisms highlight a novel dependence of cancer cells on their metabolic abnormalities to buffer oxidative stress and chemotherapeutic agents interfere with these cellular abilities. Mitochondria appear to play a significant role in maintaining cancer cell viability and alterations in metabolism seen in cancer cells aid this mitochondrial ability. Further research is needed to understand the effects of other chemotherapeutic agents on these pathways. Methotrexate inhibits multiple enzymes beyond dihydrofolate reductase. Mitochondria serve a critical role in buffering cellular oxidative stress. Metabolic derangements seen in cancer fuel this mitochondrial rescue function. Methotrexate toxicity occurs secondary to a handicapping of this buffering function. Many chemotherapeutic agents appear to have mechanisms affecting these pathways.
Collapse
Affiliation(s)
- Joshua A Hess
- Department of Internal Medicine and Pediatrics, Marshall University School of Medicine, 1600 Medical Center Drive, Huntington, WV 25701, United States
| | - Mohamad K Khasawneh
- Marshall University School of Medicine, Edwards Comprehensive Cancer Center, 1400 Hal Greer Blvd., Huntington, WV 25701, United States
| |
Collapse
|
21
|
Sadakierska-Chudy A, Filip M. A comprehensive view of the epigenetic landscape. Part II: Histone post-translational modification, nucleosome level, and chromatin regulation by ncRNAs. Neurotox Res 2014; 27:172-97. [PMID: 25516120 PMCID: PMC4300421 DOI: 10.1007/s12640-014-9508-6] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 12/02/2014] [Accepted: 12/03/2014] [Indexed: 12/31/2022]
Abstract
The complexity of the genome is regulated by epigenetic mechanisms, which act on the level of DNA, histones, and nucleosomes. Epigenetic machinery is involved in various biological processes, including embryonic development, cell differentiation, neurogenesis, and adult cell renewal. In the last few years, it has become clear that the number of players identified in the regulation of chromatin structure and function is still increasing. In addition to well-known phenomena, including DNA methylation and histone modification, new, important elements, including nucleosome mobility, histone tail clipping, and regulatory ncRNA molecules, are being discovered. The present paper provides the current state of knowledge about the role of 16 different histone post-translational modifications, nucleosome positioning, and histone tail clipping in the structure and function of chromatin. We also emphasize the significance of cross-talk among chromatin marks and ncRNAs in epigenetic control.
Collapse
Affiliation(s)
- Anna Sadakierska-Chudy
- Laboratory of Drug Addiction Pharmacology, Institute of Pharmacology Polish Academy of Sciences, Smetna 12, 31-343, Kraków, Poland,
| | | |
Collapse
|
22
|
Qin Z, Dimitrijevic A, Aswad DW. Accelerated protein damage in brains of PIMT+/- mice; a possible model for the variability of cognitive decline in human aging. Neurobiol Aging 2014; 36:1029-36. [PMID: 25465735 DOI: 10.1016/j.neurobiolaging.2014.10.036] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2014] [Revised: 10/14/2014] [Accepted: 10/27/2014] [Indexed: 12/18/2022]
Abstract
Isoaspartate formation is a common type of protein damage normally kept in check by the repair enzyme protein-L-isoaspartyl methyltransferase (PIMT). Mice with a knockout of the gene (Pcmt1) for this enzyme (KO, -/-) exhibit a pronounced neuropathology with fatal epileptic seizures at 30-60 days. Heterozygous (HZ, +/-) mice have 50% of the PIMT activity found in wild-type (WT, +/+) mice, but appear normal. To see if HZ mice exhibit accelerated aging at the molecular level, we compared brain extracts from HZ and WT mice at 8 months and 2 years with regard to PIMT activity, isoaspartate levels, and activity of an endogenous PIMT substrate, creatine kinase B. PIMT activity declined modestly with age in both genotypes. Isoaspartate was significantly higher in HZ than WT mice at 8 months and more so at 2 years, rising 5× faster in HZ males and 3× faster in females. Creatine kinase activity decreased with age and was always lower in the HZ mice. These findings suggest the individual variation of human PIMT levels may significantly influence the course of age-related central nervous system dysfunction.
Collapse
Affiliation(s)
- Zhenxia Qin
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA
| | - Aleksandra Dimitrijevic
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA
| | - Dana W Aswad
- Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, CA, USA.
| |
Collapse
|
23
|
Dimitrijevic A, Qin Z, Aswad DW. Isoaspartyl formation in creatine kinase B is associated with loss of enzymatic activity; implications for the linkage of isoaspartate accumulation and neurological dysfunction in the PIMT knockout mouse. PLoS One 2014; 9:e100622. [PMID: 24955845 PMCID: PMC4067349 DOI: 10.1371/journal.pone.0100622] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 05/29/2014] [Indexed: 01/12/2023] Open
Abstract
Isoaspartate (isoAsp) formation is a common type of spontaneous protein damage that is normally kept in check by the repair enzyme protein-L-isoaspartyl methyltransferase (PIMT). PIMT-KO (knockout) mice exhibit a pronounced neuropathology highlighted by death from an epileptic seizure at 30 to 60 days after birth. The mechanisms by which isoaspartyl damage disrupts normal brain function are incompletely understood. Proteomic analysis of the PIMT-KO mouse brain has shown that a number of key neuronal proteins accumulate high levels of isoAsp, but the extent to which their cellular functions is altered has yet to be determined. One of the major neuronal targets of PIMT is creatine kinase B (CKB), a well-characterized enzyme whose activity is relatively easy to assay. We show here that (1) the specific activity of CKB is significantly reduced in the brains of PIMT-deficient mice, (2) that in vitro aging of recombinant CKB results in significant accumulation of isoAsp sites with concomitant loss of enzymatic activity, and (3) that incubation of in vitro aged CKB with PIMT and its methyl donor S-adenosyl-L-methionine substantially repairs the aged CKB with regard to both its isoAsp content and its enzymatic activity. These results, combined with similarity in phenotypes of PIMT-KO and CKB-KO mice, suggests that loss of normal CKB structure and function contributes to the mechanisms by which isoAsp accumulation leads to CNS dysfunction in the PIMT-KO mouse.
Collapse
Affiliation(s)
- Aleksandra Dimitrijevic
- Department of Molecular Biology & Biochemistry, University of California Irvine, Irvine, California, United States of America
| | - Zhenxia Qin
- Department of Molecular Biology & Biochemistry, University of California Irvine, Irvine, California, United States of America
| | - Dana W Aswad
- Department of Molecular Biology & Biochemistry, University of California Irvine, Irvine, California, United States of America
| |
Collapse
|
24
|
Eakin CM, Miller A, Kerr J, Kung J, Wallace A. Assessing analytical methods to monitor isoAsp formation in monoclonal antibodies. Front Pharmacol 2014; 5:87. [PMID: 24808864 PMCID: PMC4010776 DOI: 10.3389/fphar.2014.00087] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 04/09/2014] [Indexed: 11/13/2022] Open
Abstract
A ubiquitous post-translational modification observed in proteins is isomerization of aspartic acid to isoaspartic acid (isoAsp). This non-enzymatic post-translational modification occurs spontaneously in proteins and plays a role in aging, autoimmune response, cancer, neurodegeneration, and other diseases. Formation of isoAsp is also a significant issue for recombinant monoclonal antibody based protein therapeutics particularly when isomerization occurs in a complementarity-determining region due to potential impact to the clinical efficacy. Here, we present and compare three analytical methods to monitor and/or quantify isoAsp formation in a monoclonal antibody. The methods include two peptide map based technologies with quantitation from either UV integration or total ion peak areas, as well as an alternative approach using IdeS digestion to generate Fc/2 and Fab’2 regions, followed by hydrophobic interaction chromatography (HIC) to separate the population of Fab’2 containing an isoAsp. The level of isoAsp detected by the peptide map and the digested-HIC methods presented here show similar trends although sample throughput varies by method.
Collapse
Affiliation(s)
| | - Amanda Miller
- Department of Analytical Sciences, Amgen Inc., Seattle WA, USA
| | - Jennifer Kerr
- Department of Analytical Sciences, Amgen Inc., Seattle WA, USA
| | - James Kung
- Department of Functional Biocharacterization, Amgen Inc., Thousand Oaks CA, USA
| | - Alison Wallace
- Department of Analytical Sciences, Amgen Inc., Seattle WA, USA
| |
Collapse
|
25
|
Qin Z, Yang J, Klassen HJ, Aswad DW. Isoaspartyl protein damage and repair in mouse retina. Invest Ophthalmol Vis Sci 2014; 55:1572-9. [PMID: 24550364 DOI: 10.1167/iovs.13-13668] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
PURPOSE To determine the propensity of retinal proteins for spontaneous damage via formation of isoaspartyl sites, a common type of protein damage that could contribute to retinal disease. METHODS Tissue extracts were obtained from retinas and brains of control mice and from mice in which the gene for protein L-isoaspartate O-methyltransferase (PIMT; an enzyme that repairs isoaspartyl protein damage) was knocked out. PIMT expression in these extracts was measured by Western blot, and its specific activity was assayed by monitoring the rate of [(3)H]methyl transfer from S-adenosyl-[methyl-(3)H]L-methionine to γ-globulin. Isoaspartate levels in extracts were measured by their capacity to accept [(3)H]methyl groups via the PIMT-catalyzed methylation reaction. To compare molecular weight distributions of isoaspartyl-rich proteins in retina versus brain, proteins from PIMT knockout (KO) and control mice were separated by SDS-PAGE and transferred to polyvinylidene difluoride (PVDF). Isoaspartyl proteins were (3)H-labeled on-blot using a PIMT overlay and imaged by autoradiography. RESULTS When normalized to the β-actin content of each tissue, retina was found to be nearly identical to brain with regard to expression and activity of PIMT and its propensity to accumulate isoaspartyl sites when PIMT is absent. The two tissues show distinct differences in the molecular weight distribution of isoaspartyl proteins. CONCLUSIONS The retina is rich in PIMT activity and contains a wide range of proteins that are highly susceptible to this type of protein damage. Recoverin may be one such protein. Isoaspartate formation, along with oxidation, should be considered as a potential source of protein dysfunction and autoimmunity in retinal disease.
Collapse
Affiliation(s)
- Zhenxia Qin
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California
| | | | | | | |
Collapse
|
26
|
Ouazia D, Levros LC, Rassart E, Desrosiers RR. Dopamine down-regulation of protein L-isoaspartyl methyltransferase is dependent on reactive oxygen species in SH-SY5Y cells. Neuroscience 2014; 267:263-76. [PMID: 24631677 DOI: 10.1016/j.neuroscience.2014.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 02/18/2014] [Accepted: 03/02/2014] [Indexed: 12/21/2022]
Abstract
Parkinson's disease (PD) is a chronic and progressive neurological disorder that is characterized by the loss of dopaminergic neurons in the substantia nigra. Dopamine, via the oxidative stress that it generates in the cytosol, could contribute to the selective loss of neurons observed in PD. Protein L-isoaspartyl methyltransferase (PIMT) is an enzyme that repairs L-isoaspartyl-containing proteins and possesses anti-apoptotic properties. PIMT expression has been shown to decrease with age. Together, these observations prompted us to investigate whether dopamine can regulate PIMT expression in SH-SY5Y neuroblastoma cells. Here, we report that dopamine down-regulated PIMT at both gene and protein levels. The same inhibition of PIMT protein level was caused by the electron transport chain inhibitor, rotenone, which was accompanied, in both cases, by an increase in cell death and reactive oxygen species (ROS) production. In fact, pre-treatment with the antioxidant N-acetyl cysteine blocked PIMT dopamine-associated down-regulation. PCMT1 promoter mapping experiments allowed the identification of two regions that showed different sensitivity to DA action. A first region localized between 61 and 94bp upstream of transcription start site was very sensitive to dopamine inhibition while a second region between 41 and 61bp appeared more resistant to dopamine inhibitory effect. The inhibition of PCMT1 promoter activity was mediated by dopamine-induced ROS since it was prevented by the hydroxyl radical scavenger N,N'-dimethylthiourea. Conversely, H2O2 inhibited in a dose-dependent manner the transcriptional activity of PCMT1 promoter. Therefore, our findings identified new molecular mechanisms, cytosolic dopamine and its resulting ROS, as inhibitors of PIMT expression. This suggests that ROS generated from cytosolic dopamine could reduce both the PCMT1 gene promoter activity and the PIMT protein level thus decreasing its capacity to repair proteins involved in apoptosis and could contribute to neuronal cell death observed in PD.
Collapse
Affiliation(s)
- D Ouazia
- Université du Québec à Montréal, Département de chimie, C.P. 8888, Succursale Centre-Ville, Montréal, Québec H3C 3P8, Canada
| | - L-C Levros
- Laboratoire de Biologie Moléculaire, Département des Sciences Biologiques, Centre BioMed, Université du Québec à Montréal, Montréal, Québec H3C 3P8, Canada
| | - E Rassart
- Laboratoire de Biologie Moléculaire, Département des Sciences Biologiques, Centre BioMed, Université du Québec à Montréal, Montréal, Québec H3C 3P8, Canada
| | - R R Desrosiers
- Université du Québec à Montréal, Département de chimie, C.P. 8888, Succursale Centre-Ville, Montréal, Québec H3C 3P8, Canada.
| |
Collapse
|
27
|
Sahoo L, Singhamahapatra A, Ramkumar V, Loganathan D. Regioselective opening of unsymmetrical cyclic anhydrides: synthesis of N-glycosylated isoasparagine and isoglutamine conjugates. RSC Adv 2014. [DOI: 10.1039/c4ra01234h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
28
|
Doyle HA, Yang ML, Raycroft MT, Gee RJ, Mamula MJ. Autoantigens: novel forms and presentation to the immune system. Autoimmunity 2013; 47:220-33. [PMID: 24191689 DOI: 10.3109/08916934.2013.850495] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
It is clear that lupus autoimmunity is marked by a variety of abnormalities, including those found at a macroscopic scale, cells and tissues, as well as more microenvironmental influences, originating at the individual cell surface through to the nucleus. The convergence of genetic, epigenetic, and perhaps environmental influences all lead to the overt clinical expression of disease, reflected by the presences of autoantibodies and tissue pathology. This review will address several specific areas that fall among the non-genetic factors that contribute to lupus autoimmunity and related syndromes. In particular, we will discuss the importance of understanding various protein post-translational modifications (PTMs), mechanisms that mediate the ability of "modified self" to trigger autoimmunity, and how these PTMs influence lupus diagnosis. Finally, we will discuss altered pathways of autoantigen presentation that may contribute to the perpetuation of chronic autoimmune disease.
Collapse
Affiliation(s)
- Hester A Doyle
- Section of Rheumatology, Department of Internal Medicine, Yale University School of Medicine , New Haven, CT , USA
| | | | | | | | | |
Collapse
|
29
|
Li XL, Li BY, Cheng M, Yu F, Yin WB, Cai Q, Zhang Z, Zhang JH, Wang JF, Zhou RH, Gao HQ. PIMT prevents the apoptosis of endothelial cells in response to glycated low density lipoproteins and protective effects of grape seed procyanidin B2. PLoS One 2013; 8:e69979. [PMID: 23922881 PMCID: PMC3724603 DOI: 10.1371/journal.pone.0069979] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 06/14/2013] [Indexed: 11/28/2022] Open
Abstract
Background The development of diabetic angiopathy is associated with profound vascular endothelial cells (VEC) dysfunction and apoptosis. Glycated low density lipoproteins (gly-LDL) continuously produced in the setting of diabetic patients play an important role in causing VEC dysfunction and apoptosis. However, the underlying molecular mechanism remains largely elusive. Protein L-isoaspartyl methyltransferase (PIMT) is a widely expressed protein repair enzyme by multiple cell types of arterial wall including VEC. Our previous proteomic studies showed that the expression of PIMT was significantly decreased in the aorta of diabetic rats as compared with control rats and treatment with grape seed procyanidin extracts significantly increased the PIMT expression in diabetic rats. We hypothesized that PIMT plays a critical role in gly-LDL induced VEC apoptosis; grape seed procyanidin B2 (GSPB2) protect against gly-LDL induced VEC apoptosis through PIMT regulation. Methods and Results HUVEC transfected negative control and PIMT siRNA were treated with or without GSPB2 (10 µmol/L) for 48 h. Moreover, HUVEC of PIMT overexpression were stimulated by gly-LDL (50 µg/ml) in the presence or absence of GSPB2 (10 µmol/L) for 48 h. Our results showed that gly-LDL downregulated PIMT expression and PIMT overexpression or GSPB2 significantly attenuated gly-LDL induced VEC apoptosis. PIMT siRNA increased VEC apoptosis with up-regulation of p53, cytochrome c release, caspase-9 and caspase-3 activation. Mechanistically, overexpression of PIMT or GSPB2 increased the phosphorylation of ERK1/2 and GSK3β in the gly-LDL induced VEC. Conclusion In summary, our study identified PIMT as a key player responsible for gly-LDL induced VEC apoptosis and GSPB2 protect against gly-LDL induced VEC apoptosis by PIMT up-regulation. Targeting PIMT including use of GSPB2 could be turned into clinical application in the fighting against diabetic vascular complications.
Collapse
Affiliation(s)
- Xiao-li Li
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Department of Geriatric Endocrinology, Qi-Lu Hospital of Shandong University, Jinan, China
- Department of Drug Purchase and Supply, Qi-Lu Hospital of Shandong University, Jinan, China
| | - Bao-ying Li
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Department of Geriatric Endocrinology, Qi-Lu Hospital of Shandong University, Jinan, China
| | - Mei Cheng
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Department of Geriatric Endocrinology, Qi-Lu Hospital of Shandong University, Jinan, China
| | - Fei Yu
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Department of Geriatric Endocrinology, Qi-Lu Hospital of Shandong University, Jinan, China
| | - Wen-bin Yin
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Department of Geriatric Endocrinology, Qi-Lu Hospital of Shandong University, Jinan, China
| | - Qian Cai
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Department of Geriatric Endocrinology, Qi-Lu Hospital of Shandong University, Jinan, China
| | - Zhen Zhang
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Department of Geriatric Endocrinology, Qi-Lu Hospital of Shandong University, Jinan, China
| | - Jian-hua Zhang
- Institute of Basic Science, Medical Science Academy of Shandong, Jinan, China
| | - Jun-fu Wang
- Institute of Basic Science, Medical Science Academy of Shandong, Jinan, China
| | - Rui-hai Zhou
- Division of Cardiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Hai-qing Gao
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Department of Geriatric Endocrinology, Qi-Lu Hospital of Shandong University, Jinan, China
- * E-mail:
| |
Collapse
|
30
|
Dho SH, Deverman BE, Lapid C, Manson SR, Gan L, Riehm JJ, Aurora R, Kwon KS, Weintraub SJ. Control of cellular Bcl-xL levels by deamidation-regulated degradation. PLoS Biol 2013; 11:e1001588. [PMID: 23823868 PMCID: PMC3692414 DOI: 10.1371/journal.pbio.1001588] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2012] [Accepted: 05/07/2013] [Indexed: 02/07/2023] Open
Abstract
Deamidation of two asparagines activates a conditional PEST sequence to target Bcl-xL for degradation. The cellular concentration of Bcl-xL is among the most important determinants of treatment response and overall prognosis in a broad range of tumors as well as an important determinant of the cellular response to several forms of tissue injury. We and others have previously shown that human Bcl-xL undergoes deamidation at two asparaginyl residues and that DNA-damaging antineoplastic agents as well as other stimuli can increase the rate of deamidation. Deamidation results in the replacement of asparginyl residues with aspartyl or isoaspartyl residues. Thus deamidation, like phosphorylation, introduces a negative charge into proteins. Here we show that the level of human Bcl-xL is constantly modulated by deamidation because deamidation, like phosphorylation in other proteins, activates a conditional PEST sequence to target Bcl-xL for degradation. Additionally, we show that degradation of deamidated Bcl-xL is mediated at least in part by calpain. Notably, we present sequence and biochemical data that suggest that deamidation has been conserved from the simplest extant metazoans through the human form of Bcl-xL, underscoring its importance in Bcl-xL regulation. Our findings strongly suggest that deamidation-regulated Bcl-xL degradation is an important component of the cellular rheostat that determines susceptibility to DNA-damaging agents and other death stimuli. Cellular levels of the pro-survival protein Bcl-xL are an important determinant of cellular susceptibility to many death stimuli, including most cancer therapies. We previously showed that human Bcl-xL undergoes deamidation – the conversion of two neutral asparaginyl side-chains into negatively charged aspartyl side-chains – a process that occurs spontaneously but is accelerated by the treatment of tumor cells with DNA-damaging agents. Here, we show that deamidation activates a hitherto undetected signal sequence within Bcl-xL that targets it for degradation by a pathway involving the proteolytic enzyme calpain. This increased degradation of Bcl-xL, and the consequent enhanced cellular susceptibility to programmed cell death, may contribute to the ability of DNA-damaging agents to kill tumors. We also demonstrate that deamidation of Bcl-xL has likely been conserved from the simplest metazoans to humans, underscoring the importance of deamidation in the regulation of Bcl-xL.
Collapse
Affiliation(s)
- So Hee Dho
- Division of Urology and The Alvin J. Siteman Cancer Center, Washington University School of Medicine, Saint Louis, Missouri, United States of America
- Laboratory of Cell Signaling, Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Yusong, Daejeon, Korea
| | - Benjamin E. Deverman
- Division of Urology and The Alvin J. Siteman Cancer Center, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Carlo Lapid
- Department of Biology, Washington University, Saint Louis, Missouri, United States of America
| | - Scott R. Manson
- Division of Urology and The Alvin J. Siteman Cancer Center, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Lu Gan
- Division of Urology and The Alvin J. Siteman Cancer Center, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Jacob J. Riehm
- Division of Urology and The Alvin J. Siteman Cancer Center, Washington University School of Medicine, Saint Louis, Missouri, United States of America
| | - Rajeev Aurora
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, Missouri, United States of America
| | - Ki-Sun Kwon
- Laboratory of Cell Signaling, Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Yusong, Daejeon, Korea
- * E-mail: (K-SK); (SJW)
| | - Steven J. Weintraub
- Division of Urology and The Alvin J. Siteman Cancer Center, Washington University School of Medicine, Saint Louis, Missouri, United States of America
- Department of Internal Medicine, Washington University School of Medicine, Saint Louis, Missouri, United States of America
- Department of Internal Medicine, St. Louis VA Medical Center–John Cochran Division, Saint Louis, Missouri, United States of America
- * E-mail: (K-SK); (SJW)
| |
Collapse
|
31
|
Mikkat S, Kischstein T, Kreutzer M, Glocker MO. Mass spectrometric peptide analysis of 2DE-separated mouse spinal cord and rat hippocampus proteins suggests an NGxG motif of importance for in vivo deamidation. Electrophoresis 2013; 34:1610-8. [DOI: 10.1002/elps.201200682] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Revised: 02/11/2013] [Accepted: 02/20/2013] [Indexed: 12/16/2022]
Affiliation(s)
| | - Timo Kischstein
- Oscar Langendorff Institute of Physiology; University Medicine Rostock; Rostock; Germany
| | - Michael Kreutzer
- Proteome Center Rostock; University Medicine Rostock; Rostock; Germany
| | | |
Collapse
|
32
|
Perna AF, Sepe I, Lanza D, Capasso R, Zappavigna S, Capasso G, Caraglia M, Ingrosso D. Hydrogen sulfide reduces cell adhesion and relevant inflammatory triggering by preventing ADAM17-dependent TNF-α activation. J Cell Biochem 2013; 114:1536-48. [DOI: 10.1002/jcb.24495] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 12/18/2012] [Indexed: 12/31/2022]
|
33
|
Yan G, Qin Q, Yi B, Chuprun K, Sun H, Huang S, Sun J. Protein-L-isoaspartate (D-aspartate) O-methyltransferase protects cardiomyocytes against hypoxia induced apoptosis through inhibiting proapoptotic kinase Mst1. Int J Cardiol 2013; 168:3291-9. [PMID: 23647599 DOI: 10.1016/j.ijcard.2013.04.045] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 02/14/2013] [Accepted: 04/06/2013] [Indexed: 01/15/2023]
Abstract
BACKGROUND Mammalian sterile 20-like kinase 1 (Mst1) is a mammalian homolog of Hippo kinase from Drosophila and it is a critical component of the Hippo signaling pathway, which regulates a variety of biological processes ranging from cell contact inhibition, organ size control, apoptosis and tumor suppression in mammals. Mst1 plays essential roles in heart disease since its activation causes cardiomyocyte apoptosis and dilated cardiomyopathy. However, the mechanism underlying Mst1 activation in the heart is not known. METHODS AND RESULTS To identify novel cardiac proteins that may regulate Mst1 activity in the heart under pathophysiological conditions, a yeast two-hybrid screening of a human heart cDNA library with a dominant-negative Mst1 (K59R) mutant used as bait was performed. As a result, protein-L-isoaspartate (D-aspartate) O-methyltransferase (PCMT1) was identified as an Mst1-interacting protein. The interaction of PCMT1 with Mst1 was confirmed by co-immunoprecipitation in both co-transfected HEK293 cells and native cardiomyocytes, in which PCMT1 interacted with the kinase domain of Mst1, but not with its C-terminal regulatory domain. Overexpression of PCMT1 did not affect the Mst1 expression, but significantly attenuated the Mst1 activation and its apoptotic effects in response to the hypoxia/reoxygenation induced injury in cardiomyocytes. Indeed, upregulation of PCMT1 by CGP3466B, a compound related to the anti-Parkinson's drug R-(-)-deprenyl with potent antiapoptotic effects, inhibited the hypoxia/reoxygenation induced Mst1 activation and cardiomyocyte apoptosis. CONCLUSIONS These findings implicate PCMT1 as a novel inhibitor of Mst1 activation in cardiomyocytes and suggest that targeting PCMT1 may prevent myocardial apoptosis through inhibition of Mst1.
Collapse
Affiliation(s)
- Guijun Yan
- Center for Translational Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA; Reproductive Medicine Center, The Affiliated Drum Tower Hospital of Nanjing University, Nanjing, China
| | | | | | | | | | | | | |
Collapse
|
34
|
Dai S, Ni W, Patananan AN, Clarke SG, Karger BL, Zhou ZS. Integrated proteomic analysis of major isoaspartyl-containing proteins in the urine of wild type and protein L-isoaspartate O-methyltransferase-deficient mice. Anal Chem 2013; 85:2423-30. [PMID: 23327623 DOI: 10.1021/ac303428h] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The formation of isoaspartyl residues (isoAsp or isoD) via either aspartyl isomerization or asparaginyl deamidation alters protein structure and potentially biological function. This is a spontaneous and nonenzymatic process, ubiquitous both in vivo and in nonbiological systems, such as in protein pharmaceuticals. In almost all organisms, protein L-isoaspartate O-methyltransferase (PIMT, EC2.1.1.77) recognizes and initiates the conversion of isoAsp back to aspartic acid. Additionally, alternative proteolytic and excretion pathways to metabolize isoaspartyl-containing proteins have been proposed but not fully explored, largely due to the analytical challenges for detecting isoAsp. We report here the relative quantitation and site profiling of isoAsp in urinary proteins from wild type and PIMT-deficient mice, representing products from excretion pathways. First, using a biochemical approach, we found that the total isoaspartyl level of proteins in urine of PIMT-deficient male mice was elevated. Subsequently, the major isoaspartyl protein species in urine from these mice were identified as major urinary proteins (MUPs) by shotgun proteomics. To enhance the sensitivity of isoAsp detection, a targeted proteomic approach using electron transfer dissociation-selected reaction monitoring (ETD-SRM) was developed to investigate isoAsp sites in MUPs. A total of 38 putative isoAsp modification sites in MUPs were investigated, with five derived from the deamidation of asparagine that were confirmed to contribute to the elevated isoAsp levels. Our findings lend experimental evidence for the hypothesized excretion pathway for isoAsp proteins. Additionally, the developed method opens up the possibility to explore processing mechanisms of isoaspartyl proteins at the molecular level, such as the fate of protein pharmaceuticals in circulation.
Collapse
Affiliation(s)
- Shujia Dai
- Barnett Institute of Chemical and Biological Analysis, Northeastern University, Boston Massachusetts 02115, United States
| | | | | | | | | | | |
Collapse
|
35
|
Patra P, Mitra S, Debnath N, Goswami A. Biochemical-, biophysical-, and microarray-based antifungal evaluation of the buffer-mediated synthesized nano zinc oxide: an in vivo and in vitro toxicity study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:16966-16978. [PMID: 23163331 DOI: 10.1021/la304120k] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Here we describe a simple, novel method of zinc oxide nanoparticle (ZNP) synthesis and physicochemical characterization. The dose-dependent antifungal effect of ZNPs, compared to that of micronized zinc oxide (MZnO), was studied on two pathogenic fungi: Aspergillus niger and Fusarium oxysporum. Superoxide dismutase (SOD) activity, ascorbate peroxidase activity, catalase activity, glutathione reductase (GR) activity, thiol content, lipid peroxidation, and proline content in ZNP-treated fungal samples were found to be elevated in comparison to the control, which strongly suggested that the antifungal effect of ZNPs was due to the generation of reactive oxygen species (ROS). Protein carbonylation, another marker of oxidative stress, was also evaluated by the dinitrophenyl hydrazine (DNPH) binding assay and Fourier transform infrared (FTIR) spectral analysis followed by Western blot and microarray analysis of fungal samples to confirm ROS generation by ZNPs. Micrographic studies for the morphological analysis of fungal samples (ZNP-treated and a control) exhibited an alteration in fungal morphology. The bioavailability of ZNPs on fungal cell was confirmed by energy-dispersive X-ray (EDX) analysis followed by high-resolution transmission electron microscopy (HR-TEM) and confocal microscopic analysis of the fungal samples. In vivo acute oral toxicity, acetylcholine esterase activity, and a fertility study using a mice model were also investigated for ZNPs. The long-term toxicity of ZNPs through intravenous injection was evaluated and compared to that of MZnO. The in vitro comparative toxicity of ZNPs and MZnO was evaluated on MRC-5 cells with the help of water-soluble tetrazolium (WST-1) and lactate dehydrogenase (LDH) assays. These results suggested that ZNPs could be used as an effective fungicide in modern medical and agricultural sciences.
Collapse
Affiliation(s)
- Prasun Patra
- Biological Sciences Division, Indian Statistical Institute, 203 B. T. Road, Kolkata 700108, India.
| | | | | | | |
Collapse
|
36
|
Doyle HA, Aswad DW, Mamula MJ. Autoimmunity to isomerized histone H2B in systemic lupus erythematosus. Autoimmunity 2012; 46:6-13. [PMID: 22967069 DOI: 10.3109/08916934.2012.710859] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Histone H2B is a common target of autoantibodies in both spontaneous and drug-induced systemic lupus erythematosus (SLE). Recent studies demonstrate that Asp(25) of histone H2B (H2B) spontaneously converts to an isoaspartic acid (isoAsp) in vivo. Our laboratory has demonstrated that the posttranslational modification of an aspartic acid to an isoaspartic acid within self-peptides renders otherwise ignored peptides immunogenic. Analysis of serum from lupus-prone mice and histone antibody positive SLE patients revealed antibodies specific to the Asp and isoAsp H2B(21-35) peptide, and that the expression of these antibodies is dependent on TLR9. IsoAsp H2B(21-35) is immunogenic in non-autoimmune prone mice and mice lacking the ability to repair isoAsp have significantly reduced levels of antibodies to H2B. Asp H2B(21-35) incubated at physiological temperatures and pH acquires the isoAsp modification, demonstrating that H2B(21-35) is prone to spontaneous isoAsp formation in vivo. Autoimmunity to isoAsp H2B suggests that this form of the autoantigen may be critical in the induction of anti-histone autoantibodies in human SLE and in murine models of disease.
Collapse
Affiliation(s)
- Hester A Doyle
- Department of Rheumatology, Yale University School of Medicine, New Haven, Connecticut 06520-8031, USA
| | | | | |
Collapse
|
37
|
Abstract
Many of the best-studied actin regulatory proteins use non-covalent means to modulate the properties of actin. Yet, actin is also susceptible to covalent modifications of its amino acids. Recent work is increasingly revealing that actin processing and its covalent modifications regulate important cellular events. In addition, numerous pathogens express enzymes that specifically use actin as a substrate to regulate their hosts' cells. Actin post-translational alterations have been linked to different normal and disease processes and the effects associated with metabolic and environmental stressors. Herein, we highlight specific co-translational and post-translational modifications of actin and discuss the current understanding of the role that these modifications play in regulating actin.
Collapse
Affiliation(s)
- Jonathan R Terman
- Department of Neuroscience, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| | | |
Collapse
|
38
|
Dutta T, Banerjee S, Soren D, Lahiri S, Sengupta S, Rasquinha JA, Ghosh AK. Regulation of Enzymatic Activity by Deamidation and Their Subsequent Repair by Protein l-isoaspartyl Methyl Transferase. Appl Biochem Biotechnol 2012; 168:2358-75. [DOI: 10.1007/s12010-012-9942-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 10/05/2012] [Indexed: 01/19/2023]
|
39
|
MacKay KB, Lowenson JD, Clarke SG. Wortmannin reduces insulin signaling and death in seizure-prone Pcmt1-/- mice. PLoS One 2012; 7:e46719. [PMID: 23071621 PMCID: PMC3465263 DOI: 10.1371/journal.pone.0046719] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 09/01/2012] [Indexed: 12/23/2022] Open
Abstract
L-isoaspartyl (D-aspartyl) O-methyltransferase deficient mice (Pcmt1−/−) accumulate isomerized aspartyl residues in intracellular proteins until their death due to seizures at approximately 45 days. Previous studies have shown that these mice have constitutively activated insulin signaling in their brains, and that these brains are 20–30% larger than those from age-matched wild-type animals. To determine whether insulin pathway activation and brain enlargement is responsible for the fatal seizures, we administered wortmannin, an inhibitor of the phosphoinositide 3-kinase that catalyzes an early step in the insulin pathway. Oral wortmannin reduced the average brain size in the Pcmt1−/− animals to within 6% of the wild-type DMSO administered controls, and nearly doubled the lifespan of Pcmt1−/− at 60% survival of the original population. Immunoblotting revealed significant decreases in phosphorylation of Akt, PDK1, and mTOR in Pcmt1−/− mice and Akt and PDK1 in wild-type animals upon treatment with wortmannin. These data suggest activation of the insulin pathway and its resulting brain enlargement contributes to the early death of Pcmt1−/− mice, but is not solely responsible for the early death observed in these animals.
Collapse
Affiliation(s)
- Kennen B. MacKay
- Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California Los Angeles, Los Angeles, California, United States of America
| | - Jonathan D. Lowenson
- Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California Los Angeles, Los Angeles, California, United States of America
| | - Steven G. Clarke
- Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California Los Angeles, Los Angeles, California, United States of America
- * E-mail:
| |
Collapse
|
40
|
Lee JC, Kang SU, Jeon Y, Park JW, You JS, Ha SW, Bae N, Lubec G, Kwon SH, Lee JS, Cho EJ, Han JW. Protein L-isoaspartyl methyltransferase regulates p53 activity. Nat Commun 2012; 3:927. [PMID: 22735455 PMCID: PMC3621463 DOI: 10.1038/ncomms1933] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 05/28/2012] [Indexed: 02/06/2023] Open
Abstract
Protein methylation plays important roles in most, if not all, cellular processes. Lysine and arginine methyltransferases are known to regulate the function of histones and non-histone proteins through the methylation of specific sites. However, the role of the carboxyl-methyltransferase protein L-isoaspartyl methyltransferase (PIMT) in the regulation of protein functions is relatively less understood. Here we show that PIMT negatively regulates the tumour suppressor protein p53 by reducing p53 protein levels, thereby suppressing the p53-mediated transcription of target genes. In addition, PIMT depletion upregulates the proapoptotic and checkpoint activation functions of p53. Moreover, PIMT destabilizes p53 by enhancing the p53–HDM2 interaction. These PIMT effects on p53 stability and activity are attributed to the PIMT-mediated methylation of p53 at isoaspartate residues 29 and 30. Our study provides new insight into the molecular mechanisms by which PIMT suppresses the p53 activity through carboxyl methylation, and suggests a therapeutic target for cancers. Protein L-isoaspartyl methyltransferase (PIMT) is a carboxyl methyltransferase, but its role in regulating the tumour suppressor p53 is unclear. Here, PIMT is shown to methylate p53, obstructing the tumour suppressor function of p53 through reduced protein levels and stability.
Collapse
Affiliation(s)
- Jae-Cheol Lee
- Research Center for Epigenome Regulation, School of Pharmacy, Sungkyunkwan University, Suwon 440-746, Republic of Korea
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Capasso R, Sambri I, Cimmino A, Salemme S, Lombardi C, Acanfora F, Satta E, Puppione DL, Perna AF, Ingrosso D. Homocysteinylated albumin promotes increased monocyte-endothelial cell adhesion and up-regulation of MCP1, Hsp60 and ADAM17. PLoS One 2012; 7:e31388. [PMID: 22319627 PMCID: PMC3272033 DOI: 10.1371/journal.pone.0031388] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 01/06/2012] [Indexed: 11/19/2022] Open
Abstract
Rationale The cardiovascular risk factor homocysteine is mainly bound to proteins in human plasma, and it has been hypothesized that homocysteinylated proteins are important mediators of the toxic effects of hyperhomocysteinemia. It has been recently demonstrated that homocysteinylated proteins are elevated in hemodialysis patients, a high cardiovascular risk population, and that homocysteinylated albumin shows altered properties. Objective Aim of this work was to investigate the effects of homocysteinylated albumin - the circulating form of this amino acid, utilized at the concentration present in uremia - on monocyte adhesion to a human endothelial cell culture monolayer and the relevant molecular changes induced at both cell levels. Methods and Results Treated endothelial cells showed a significant increase in monocyte adhesion. Endothelial cells showed after treatment a significant, specific and time-dependent increase in ICAM1 and VCAM1. Expression profiling and real time PCR, as well as protein analysis, showed an increase in the expression of genes encoding for chemokines/cytokines regulating the adhesion process and mediators of vascular remodeling (ADAM17, MCP1, and Hsp60). The mature form of ADAM17 was also increased as well as Tnf-α released in the cell medium. At monocyte level, treatment induced up-regulation of ICAM1, MCP1 and its receptor CCR2. Conclusions Treatment with homocysteinylated albumin specifically increases monocyte adhesion to endothelial cells through up-regulation of effectors involved in vascular remodeling.
Collapse
Affiliation(s)
- Rosanna Capasso
- Department of Biochemistry and Biophysics “F. Cedrangolo”, School of Medicine, Second University of Naples, Naples, Italy
| | - Irene Sambri
- Department of Biochemistry and Biophysics “F. Cedrangolo”, School of Medicine, Second University of Naples, Naples, Italy
| | - Amelia Cimmino
- Institute of Genetics and Biophysics, National Research Council, Naples, Italy
| | - Sofia Salemme
- Department of Biochemistry and Biophysics “F. Cedrangolo”, School of Medicine, Second University of Naples, Naples, Italy
| | - Cinzia Lombardi
- First Division of Nephrology, School of Medicine, Second University of Naples, Naples, Italy
| | - Filomena Acanfora
- First Division of Nephrology, School of Medicine, Second University of Naples, Naples, Italy
| | - Ersilia Satta
- First Division of Nephrology, School of Medicine, Second University of Naples, Naples, Italy
| | - Donald L. Puppione
- The Molecular Biology Institute, University of California Los Angeles, Los Angeles, California, United States of America
| | - Alessandra F. Perna
- Cardiovascular Research Centre, School of Medicine, Second University of Naples, Naples, Italy
- First Division of Nephrology, School of Medicine, Second University of Naples, Naples, Italy
- * E-mail:
| | - Diego Ingrosso
- Department of Biochemistry and Biophysics “F. Cedrangolo”, School of Medicine, Second University of Naples, Naples, Italy
- Cardiovascular Research Centre, School of Medicine, Second University of Naples, Naples, Italy
| |
Collapse
|
42
|
Sambri I, Capasso R, Pucci P, Perna AF, Ingrosso D. The microRNA 15a/16-1 cluster down-regulates protein repair isoaspartyl methyltransferase in hepatoma cells: implications for apoptosis regulation. J Biol Chem 2011; 286:43690-43700. [PMID: 22033921 DOI: 10.1074/jbc.m111.290437] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Asparaginyl deamidation, a spontaneous protein post-biosynthetic modification, determines isoaspartyl formation and structure-function impairment. The isoaspartyl protein carboxyl-O-methyltransferase (PCMT1; EC 2.1.1.77) catalyzes the repair of the isopeptide bonds at isoaspartyl sites, preventing deamidation-related functional impairment. Protein deamidation affects key apoptosis mediators, such as BclxL, thus increasing susceptibility to apoptosis, whereas PCMT1 activity may effectively counteract such alterations. The aim of this work was to establish the role of RNAi as a potential mechanism for regulating PCMT1 expression and its possible implications in apoptosis. We investigated the regulatory properties of the microRNA 15a/16-1 cluster on PCMT1 expression on HepG2 cells. MicroRNA 15a or microRNA 16-1 transfection, as well as their relevant antagonists, showed that PCMT1 is effectively regulated by this microRNA cluster. The direct interaction of these two microRNAs with the seed sequence at the 3' UTR of PCMT1 transcripts was demonstrated by the luciferase assay system. The role of PCMT1 down-regulation in conditioning the susceptibility to apoptosis was investigated using various specific siRNA or shRNA approaches, to prevent non-PCMT1-specific pleiotropic effects to take place. We found that PCMT1 silencing is associated with an increase of the BclxL isoform reported to be inactivated by deamidation, thus making cells more susceptible to apoptosis induced by cisplatinum. We conclude that PCMT1 is effectively regulated by the microRNA 15a/16-1 cluster and is involved in apoptosis by preserving the structural stability and biological function of BclxL from deamidation. Control of PCMT1 expression by microRNA 15a/16-1 may thus represent a late checkpoint in apoptosis regulation.
Collapse
Affiliation(s)
- Irene Sambri
- Department of Biochemistry and Biophysics, Second University of Naples, Naples 80138, Italy
| | - Rosanna Capasso
- Department of Biochemistry and Biophysics, Second University of Naples, Naples 80138, Italy
| | - Piero Pucci
- Ceinge, Advanced Biotechnologies and School of Life Science, "Federico II" University, Naples 80138, Italy
| | - Alessandra F Perna
- First Division of Nephrology, School of Medicine and Surgery, Second University of Naples, Naples 80138, Italy
| | - Diego Ingrosso
- Department of Biochemistry and Biophysics, Second University of Naples, Naples 80138, Italy.
| |
Collapse
|
43
|
Wang L, Chen G. Current advances in the application of proteomics in apoptosis research. SCIENCE CHINA-LIFE SCIENCES 2011; 54:209-19. [DOI: 10.1007/s11427-010-4123-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Accepted: 05/26/2010] [Indexed: 01/18/2023]
|
44
|
Ni W, Dai S, Karger BL, Zhou ZS. Analysis of isoaspartic Acid by selective proteolysis with Asp-N and electron transfer dissociation mass spectrometry. Anal Chem 2011; 82:7485-91. [PMID: 20712325 DOI: 10.1021/ac101806e] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A ubiquitous yet underappreciated protein post-translational modification, isoaspartic acid (isoAsp, isoD, or beta-Asp), generated via the deamidation of asparagine or isomerization of aspartic acid in proteins, plays a diverse and crucial role in aging, as well as autoimmune, cancer, neurodegeneration, and other diseases. In addition, formation of isoAsp is a major concern in protein pharmaceuticals, as it may lead to aggregation or activity loss. The scope and significance of isoAsp have, up to now, not been fully explored, as an unbiased screening of isoAsp at low abundance remains challenging. This difficulty is due to the subtle difference in the physicochemical properties between isoAsp and Asp, e.g., identical mass. In contrast, endoprotease Asp-N (EC 3.4.24.33) selectively cleaves aspartyl peptides but not the isoaspartyl counterparts. As a consequence, isoaspartyl peptides can be differentiated from those containing Asp and also enriched by Asp-N digestion. Subsequently, the existence and site of isoaspartate can be confirmed by electron transfer dissociation (ETD) mass spectrometry. As little as 0.5% of isoAsp was detected in synthetic beta-amyloid and cytochrome c peptides, even though both were initially assumed to be free of isoAsp. Taken together, our approach should expedite the unbiased discovery of isoAsp.
Collapse
Affiliation(s)
- Wenqin Ni
- Barnett Institute of Chemical and Biological Analysis and Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, USA
| | | | | | | |
Collapse
|
45
|
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.
Collapse
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
| | | | | | | | | |
Collapse
|
46
|
Khare S, Gomez T, Clarke SG. Defective responses to oxidative stress in protein l-isoaspartyl repair-deficient Caenorhabditis elegans. Mech Ageing Dev 2009; 130:670-80. [PMID: 19682488 PMCID: PMC2757507 DOI: 10.1016/j.mad.2009.08.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 06/19/2009] [Accepted: 08/01/2009] [Indexed: 12/16/2022]
Abstract
We have shown that Caenorhabditis elegans lacking the PCM-1 protein repair l-isoaspartyl methyltransferase are more sensitive to oxidative stress than wild-type nematodes. Exposure to the redox-cycling quinone juglone upon exit from dauer diapause results in defective egg-laying (Egl phenotype) in the pcm-1 mutants only. Treatment with paraquat, a redox-cycling dipyridyl, causes a more severe developmental delay at the second larval stage in pcm-1 mutants than in wild-type nematodes. Finally, exposure to homocysteine and homocysteine thiolactone, molecules that can induce oxidative stress via distinct mechanisms, results in a more pronounced delay in development at the first larval stage in pcm-1 mutants than in wild-type animals. Homocysteine treatment also induced the Egl phenotype in mutant but not wild-type nematodes. All of the effects of these agents were reversed upon addition of vitamin C, indicating that the developmental delay and egg-laying defects result from oxidative stress. Furthermore, we have demonstrated that a mutation in the gene encoding the insulin-like receptor DAF-2 suppresses the Egl phenotype in pcm-1 mutants treated with juglone. Our results support a role of PCM-1 in the cellular responses mediated by the DAF-2 insulin-like signaling pathway in C. elegans for optimal protection against oxidative stress.
Collapse
Affiliation(s)
- Shilpi Khare
- Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Tara Gomez
- Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Steven G. Clarke
- Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| |
Collapse
|