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Majumdar R, Tavakoli Tameh A, Arya SB, Parent CA. Exosomes mediate LTB4 release during neutrophil chemotaxis. PLoS Biol 2021; 19:e3001271. [PMID: 34232954 PMCID: PMC8262914 DOI: 10.1371/journal.pbio.3001271] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/07/2021] [Indexed: 12/22/2022] Open
Abstract
Leukotriene B4 (LTB4) is secreted by chemotactic neutrophils, forming a secondary gradient that amplifies the reach of primary chemoattractants. This strategy increases the recruitment range for neutrophils and is important during inflammation. Here, we show that LTB4 and its synthesizing enzymes localize to intracellular multivesicular bodies, which, upon stimulation, release their content as exosomes. Purified exosomes can activate resting neutrophils and elicit chemotactic activity in an LTB4 receptor-dependent manner. Inhibition of exosome release leads to loss of directional motility with concomitant loss of LTB4 release. Our findings establish that the exosomal pool of LTB4 acts in an autocrine fashion to sensitize neutrophils towards the primary chemoattractant, and in a paracrine fashion to mediate the recruitment of neighboring neutrophils in trans. We envision that this mechanism is used by other signals to foster communication between cells in harsh extracellular environments. Concerns have emerged about the immunoelectron microscopy results originally reported in the article by Majumdar and colleagues [1]. In addition, errors were made in the scale bars reported in Figs 2H and 3D of the same article. Accordingly, this article has been retracted. We are grateful for the opportunity to republish a version of this article in which the electron microscopy data have been removed. None of the major conclusions attained in the original article are affected by the removal of the contentious data. We sincerely apologize to PLOS Biology and the scientific community at large for this occurrence.
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Affiliation(s)
- Ritankar Majumdar
- Laboratory of Cellular and Molecular Biology Center for Cancer Research, NCI, NIH, Bethesda, Maryland, United States of America
| | - Aidin Tavakoli Tameh
- Laboratory of Cellular and Molecular Biology Center for Cancer Research, NCI, NIH, Bethesda, Maryland, United States of America
| | - Subhash B. Arya
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, United States of America
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Carole A. Parent
- Laboratory of Cellular and Molecular Biology Center for Cancer Research, NCI, NIH, Bethesda, Maryland, United States of America
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, United States of America
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- Rogel Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- * E-mail:
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2
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Stokes AH, Franklin K, Fisher DE, Posobiec LM, Binazon O, Tripathi N, Ringenberg MA, Charlap J, Ziejewski MK, Vemireddi V, Khanna Weiss P, Majumdar R, Bouzya B, Donner MN, Rodriguez LA, Baumeister J. Repeated Dose Toxicity Study and Developmental and Reproductive Toxicology Studies of a Respiratory Syncytial Virus Candidate Vaccine in Rabbits and Rats. Int J Toxicol 2021; 40:125-142. [PMID: 33517807 DOI: 10.1177/1091581820985782] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infections, and vaccines are needed to treat young children and older adults. One of GSK's candidate vaccines for RSV contains recombinant RSVPreF3 protein maintained in the prefusion conformation. The differences in immune function of young children and older adults potentially require different vaccine approaches. For young children, anti-RSV immunity can be afforded during the first months of life by vaccinating the pregnant mother during the third trimester with unadjuvanted RSVPreF3, which results in protection of the infant due to the transplacental passage of anti-RSV maternal antibodies. For older adults with a waning immune response, the approach is to adjuvant the RSVPreF3 vaccine with AS01 to elicit a more robust immune response.The local and systemic effects of biweekly intramuscular injections of the RSVPreF3 vaccine (unadjuvanted, adjuvanted with AS01, or coadministered with a diphtheria-tetanus-acellular pertussis vaccine) was tested in a repeated dose toxicity study in rabbits. After three intramuscular doses, the only changes observed were those commonly related to a vaccine-elicited inflammatory reaction. Subsequently, the effects of unadjuvanted RSVPreF3 vaccine on female fertility, embryo-fetal, and postnatal development of offspring were evaluated in rats and rabbits. There were no effects on pregnancy, delivery, lactation, or the pre- and postnatal development of offspring.In conclusion, the RSVPreF3 vaccine was well-tolerated locally and systemically and was not associated with any adverse effects on female reproductive function or on the pre- and postnatal growth and development of offspring.
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Affiliation(s)
| | | | | | | | | | | | | | - Jeffrey Charlap
- Charles River Laboratories, Horsham, PA, USA
- Current affiliation: Chevron, San Ramon, CA, USA
| | | | | | - Payal Khanna Weiss
- 201915Covance Laboratories Inc, Chantilly, VA, USA
- Current affiliation: DEFTEC Corporation, Inc., Chantilly, VA ,USA
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3
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Steen K, Chen D, Wang F, Majumdar R, Chen S, Kumar S, Lombard DB, Weigert R, Zieman AG, Parent CA, Coulombe PA. A role for keratins in supporting mitochondrial organization and function in skin keratinocytes. Mol Biol Cell 2020; 31:1103-1111. [PMID: 32213122 PMCID: PMC7353162 DOI: 10.1091/mbc.e19-10-0565] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mitochondria fulfill essential roles in ATP production, metabolic regulation, calcium signaling, generation of reactive oxygen species (ROS), and additional determinants of cellular health. Recent studies have highlighted a role for mitochondria during cell differentiation, including in skin epidermis. The observation of oxidative stress in keratinocytes from Krt16 null mouse skin, a model for pachyonychia congenita (PC)–associated palmoplantar keratoderma, prompted us to examine the role of Keratin (K) 16 protein and its partner K6 in regulating the structure and function of mitochondria. Electron microscopy revealed major anomalies in mitochondrial ultrastructure in late stage, E18.5, Krt6a/Krt6b null embryonic mouse skin. Follow-up studies utilizing biochemical, metabolic, and live imaging readouts showed that, relative to controls, skin keratinocytes null for Krt6a/Krt6b or Krt16 exhibit elevated ROS, reduced mitochondrial respiration, intracellular distribution differences, and altered movement of mitochondria within the cell. These findings highlight a novel role for K6 and K16 in regulating mitochondrial morphology, dynamics, and function and shed new light on the causes of oxidative stress observed in PC and related keratin-based skin disorders.
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Affiliation(s)
- Kaylee Steen
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Desu Chen
- Laboratory for Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Fengrong Wang
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Ritankar Majumdar
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Song Chen
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Surinder Kumar
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - David B Lombard
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109.,Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109
| | - Roberto Weigert
- Laboratory for Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Abigail G Zieman
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Carole A Parent
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109.,Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109.,Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109
| | - Pierre A Coulombe
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109.,Department of Dermatology, University of Michigan Medical School, Ann Arbor, MI 48109.,Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109
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Majumdar R, Steen K, Coulombe PA, Parent CA. Non-canonical processes that shape the cell migration landscape. Curr Opin Cell Biol 2019; 57:123-134. [PMID: 30852463 PMCID: PMC7087401 DOI: 10.1016/j.ceb.2018.12.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 12/14/2018] [Accepted: 12/21/2018] [Indexed: 12/19/2022]
Abstract
Migration is a vital, intricate, and multi-faceted process that involves the entire cell, entails the integration of multiple external cues and, at times, necessitates high-level coordination among fields of cells that can be physically attached or not, depending on the physiological setting. Recent advances have highlighted the essential role of cellular components that have not been traditionally considered when studying cell migration. This review details how much we recently learned by studying the role of intermediate filaments, the nucleus, extracellular vesicles, and mitochondria during cell migration.
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Affiliation(s)
- Ritankar Majumdar
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Kaylee Steen
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Pierre A Coulombe
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Dermatology, University of Michigan, Ann Arbor, MI 48109, USA; Rogel Cancer Center Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Carole A Parent
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA; Rogel Cancer Center Michigan Medicine, University of Michigan, Ann Arbor, MI 48109, USA.
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5
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Saunders CA, Majumdar R, Molina Y, Subramanian BC, Parent CA. Genetic manipulation of PLB-985 cells and quantification of chemotaxis using the underagarose assay. Methods Cell Biol 2018; 149:31-56. [PMID: 30616826 DOI: 10.1016/bs.mcb.2018.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Neutrophils are the most common leukocyte in human blood and are the first cells to respond to injury and infection. Improper neutrophil chemotaxis can have deleterious effects on human health, including autoimmune diseases, poor innate immune response, and cancer. Therefore, gaining a better understanding of the signaling pathways governing chemotactic responses in these cells is important. One of the main challenges of working with primary human neutrophils is their short lifespan (about 1 day), making genetic manipulations not feasible. PLB-985 cells, which are pluripotent hematopoietic cells that can easily be differentiated to neutrophil-like cells, are amenable to genetic manipulations, including the expression of fluorescently tagged proteins-of-interest (POI) and gene editing using the CRISPR/CAS9 system to delete genes-of-interest (GOI). The use of PLB-985 cells can therefore greatly facilitate our understanding of the molecular mechanisms governing neutrophil biology during chemotaxis and serve as a good system to complement results gained from pharmacological inhibition of primary neutrophils. To better study the role and localization of proteins during chemotaxis, the underagarose assay has become a widely used and quantitative assay for measuring several aspects of chemotaxis. The objective of this chapter is to provide protocols for (1) the generation of genetically altered PLB-985 cell lines, (2) the set-up of an underagarose chemotaxis assay, and (3) the analysis of cell movement in chemotactic gradients from an underagarose experiment.
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Affiliation(s)
- Cosmo A Saunders
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, United States
| | - Ritankar Majumdar
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, United States
| | - Yaniris Molina
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, United States; Cancer Research Summer Internship Program, Cancer Biology, University of Michigan, Ann Arbor, MI, United States
| | - Bhagawat C Subramanian
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, United States
| | - Carole A Parent
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, United States.
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6
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Kriebel PW, Majumdar R, Jenkins LM, Senoo H, Wang W, Ammu S, Chen S, Narayan K, Iijima M, Parent CA. Extracellular vesicles direct migration by synthesizing and releasing chemotactic signals. J Cell Biol 2018; 217:2891-2910. [PMID: 29884750 PMCID: PMC6080930 DOI: 10.1083/jcb.201710170] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 03/14/2018] [Accepted: 05/11/2018] [Indexed: 02/06/2023] Open
Abstract
Kriebel et al. show that Dictyostelium cells release extracellular vesicles (EVs) that not only contain the chemoattractant cAMP but also actively synthesize and release cAMP to promote chemotaxis. They show that the EV release of cAMP is mediated by the ABCC8 transporter. Chemotactic signals are relayed to neighboring cells through the secretion of additional chemoattractants. We previously showed in Dictyostelium discoideum that the adenylyl cyclase A, which synthesizes the chemoattractant cyclic adenosine monophosphate (cAMP), is present in the intraluminal vesicles of multivesicular bodies (MVBs) that coalesce at the back of cells. Using ultrastructural reconstructions, we now show that ACA-containing MVBs release their contents to attract neighboring cells. We show that the released vesicles are capable of directing migration and streaming and are central to chemotactic signal relay. We demonstrate that the released vesicles not only contain cAMP but also can actively synthesize and release cAMP to promote chemotaxis. Through proteomic, pharmacological, and genetic approaches, we determined that the vesicular cAMP is released via the ABCC8 transporter. Together, our findings show that extracellular vesicles released by D. discoideum cells are functional entities that mediate signal relay during chemotaxis and streaming.
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Affiliation(s)
- Paul W Kriebel
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Ritankar Majumdar
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD .,Department of Pharmacology, University of Michigan, Ann Arbor, MI
| | - Lisa M Jenkins
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Hiroshi Senoo
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Weiye Wang
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Sonia Ammu
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Song Chen
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD.,Department of Pharmacology, University of Michigan, Ann Arbor, MI.,Institute for Physical Science and Technology, University of Maryland, College Park, MD
| | - Kedar Narayan
- Center for Molecular Microscopy, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD.,Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Frederick, MD
| | - Miho Iijima
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Carole A Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD .,Department of Pharmacology, University of Michigan, Ann Arbor, MI.,Institute for Physical Science and Technology, University of Maryland, College Park, MD
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7
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Subramanian BC, Majumdar R, Parent CA. The role of the LTB 4-BLT1 axis in chemotactic gradient sensing and directed leukocyte migration. Semin Immunol 2018; 33:16-29. [PMID: 29042024 DOI: 10.1016/j.smim.2017.07.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 06/07/2017] [Accepted: 07/13/2017] [Indexed: 12/11/2022]
Abstract
Directed leukocyte migration is a hallmark of inflammatory immune responses. Leukotrienes are derived from arachidonic acid and represent a class of potent lipid mediators of leukocyte migration. In this review, we summarize the essential steps leading to the production of LTB4 in leukocytes. We discuss the recent findings on the exosomal packaging and transport of LTB4 in the context of chemotactic gradients formation and regulation of leukocyte recruitment. We also discuss the dynamic roles of the LTB4 receptors, BLT1 and BLT2, in mediating chemotactic signaling in leukocytes and contrast them to other structurally related leukotrienes that bind to distinct GPCRs. Finally, we highlight the specific roles of the LTB4-BLT1 axis in mediating signal-relay between chemotaxing neutrophils and its potential contribution to a wide variety of inflammatory conditions including tumor progression and metastasis, where LTB4 is emerging as a key signaling component.
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Affiliation(s)
- Bhagawat C Subramanian
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892, United States.
| | - Ritankar Majumdar
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892, United States; Department of Pharmacology, University of Michigan School of Medicine, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, United States.
| | - Carole A Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892, United States; Department of Pharmacology, University of Michigan School of Medicine, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, United States.
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8
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Szatmary AC, Nossal R, Parent CA, Majumdar R. Modeling neutrophil migration in dynamic chemoattractant gradients: assessing the role of exosomes during signal relay. Mol Biol Cell 2017; 28:3457-3470. [PMID: 28954858 PMCID: PMC5687044 DOI: 10.1091/mbc.e17-05-0298] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 09/15/2017] [Accepted: 09/19/2017] [Indexed: 01/07/2023] Open
Abstract
Cells chemotaxing in decaying gradients of primary chemoattractants maintain their
chemotactic response by releasing secondary chemoattractants. Steep, local gradients
of secondary chemoattractants can be reached with molecules of higher hydrophobicity,
whereas temporal stability can be achieved by packaging in extracellular
vesicles. Migrating cells often exhibit signal relay, a process in which cells migrating in
response to a chemotactic gradient release a secondary chemoattractant to enhance
directional migration. In neutrophils, signal relay toward the primary
chemoattractant N-formylmethionyl-leucyl-phenylalanine (fMLP) is mediated by
leukotriene B4 (LTB4). Recent evidence suggests that the
release of LTB4 from cells occurs through packaging in exosomes. Here we
present a mathematical model of neutrophil signal relay that focuses on
LTB4 and its exosome-mediated secretion. We describe neutrophil
chemotaxis in response to a combination of a defined gradient of fMLP and an evolving
gradient of LTB4, generated by cells in response to fMLP. Our model
enables us to determine the gradient of LTB4 arising either through
directed secretion from cells or through time-varying release from exosomes. We
predict that the secondary release of LTB4 increases recruitment range and
show that the exosomes provide a time delay mechanism that regulates the development
of LTB4 gradients. Additionally, we show that under decaying primary
gradients, secondary gradients are more stable when secreted through exosomes as
compared with direct secretion. Our chemotactic model, calibrated from observed
responses of cells to gradients, thereby provides insight into chemotactic signal
relay in neutrophils during inflammation.
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Affiliation(s)
- Alex C Szatmary
- Division of Basic and Translational Biophysics, National Institute of Child Health and Human Development, Rockville, MD 20847
| | - Ralph Nossal
- Division of Basic and Translational Biophysics, National Institute of Child Health and Human Development, Rockville, MD 20847
| | - Carole A Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Ritankar Majumdar
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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9
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Abstract
Leukotriene B4 (LTB4) is secreted by chemotactic neutrophils, forming a secondary gradient that amplifies the reach of primary chemoattractants. This strategy increases the recruitment range for neutrophils and is important during inflammation. Here, we show that LTB4 and its synthesizing enzymes localize to intracellular multivesicular bodies that, upon stimulation, release their content as exosomes. Purified exosomes can activate resting neutrophils and elicit chemotactic activity in a LTB4 receptor-dependent manner. Inhibition of exosome release leads to loss of directional motility with concomitant loss of LTB4 release. Our findings establish that the exosomal pool of LTB4 acts in an autocrine fashion to sensitize neutrophils towards the primary chemoattractant, and in a paracrine fashion to mediate the recruitment of neighboring neutrophils in trans. We envision that this mechanism is used by other signals to foster communication between cells in harsh extracellular environments.
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Affiliation(s)
- Ritankar Majumdar
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Aidin Tavakoli Tameh
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Carole A. Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
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10
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Abstract
How chemoattractant gradients form and persist in complex tissues is a key question in cell migration. Two studies now show that CXCR7 acts as a sink in the migrating zebrafish lateral line primordium to generate SDF1 gradients.
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Affiliation(s)
- Konstadinos Moissoglu
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ritankar Majumdar
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Carole A Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
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Majumdar R, Sixt M, Parent CA. New paradigms in the establishment and maintenance of gradients during directed cell migration. Curr Opin Cell Biol 2014; 30:33-40. [PMID: 24959970 DOI: 10.1016/j.ceb.2014.05.010] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 05/27/2014] [Indexed: 11/16/2022]
Abstract
Directional guidance of migrating cells is relatively well explored in the reductionist setting of cell culture experiments. Here spatial gradients of chemical cues as well as gradients of mechanical substrate characteristics prove sufficient to attract single cells as well as their collectives. How such gradients present and act in the context of an organism is far less clear. Here we review recent advances in understanding how guidance cues emerge and operate in complex physiological settings.
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Affiliation(s)
- Ritankar Majumdar
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
| | - Michael Sixt
- IST Austria (Institute of Science and Technology Austria), 3400 Klostemeuburg, Austria
| | - Carole A Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States.
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Nath D, Majumdar R, Kalra MS. Thermonuclear Fusion Reactivities for Drifting Tri-Maxwellian Ion Velocity Distributions. J Fusion Energ 2013. [DOI: 10.1007/s10894-013-9594-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Saha S, Majumdar R, Hussain A, Dighe RR, Chakravarty AR. Biotin-conjugated tumour-targeting photocytotoxic iron(III) complexes. Philos Trans A Math Phys Eng Sci 2013; 371:20120190. [PMID: 23776297 DOI: 10.1098/rsta.2012.0190] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Iron(III) complexes [FeL(B)] (1-4) of a tetradentate phenolate-based ligand (H3L) and biotin-conjugated dipyridophenazine bases (B), viz. 7-aminodipyrido [3,2-a:2',3'-c]-phenazine (dppza in 1), (N-dipyrido[3,2-a:2',3'-c]-phenazino)amidobiotin (dppzNB in 2), dipyrido [3,2-a:2',3'-c]-phenazine-11-carboxylic acid (dppzc in 3) and 2-((2-biotinamido)ethyl) amido-dipyrido[3,2-a:2',3'-c]-phenazine (dppzCB in 4) are prepared, characterized and their interaction with streptavidin and DNA and their photocytotoxicity and cellular uptake in various cells studied. The high-spin iron(III) complexes display Fe(III)/Fe(II) redox couple near -0.7 V versus saturated calomel electrode in dimethyl sulfoxide-0.1 M tetrabutylammonium perchlorate. The complexes show non-specific interaction with DNA as determined from the binding studies. Complexes with appended biotin moiety show similar binding to streptavidin as that of free biotin, suggesting biotin conjugation to dppz does not cause any loss in its binding affinity to streptavidin. The photocytotoxicity of the complexes is tested in HepG2, HeLa and HEK293 cell lines. Complex 2 shows higher photocytotoxicity in HepG2 cells than in HeLa or HEK293, forming reactive oxygen species. This effect is attributed to the presence of overexpressed sodium-dependent multi-vitamin transporters in HepG2 cells. Microscopic studies in HepG2 cells show internalization of the biotin complexes 2 and 4 essentially occurring by receptor-mediated endocytosis, which is similar to that of native biotin and biotin fluorescein isothiocyanate conjugate.
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Affiliation(s)
- Sounik Saha
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
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Majumdar R, Donnellan CF. Letter: are we ready to dismiss use of enteral nutrition in cirrhotic patients with jaundice? Aliment Pharmacol Ther 2012; 36:684; author reply 684-5. [PMID: 22966797 DOI: 10.1111/j.1365-2036.2012.05199.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Majumdar R, Railkar R, Dighe RR. The antibodies against the computationally designed mimic of the glycoprotein hormone receptor transmembrane domain provide insights into receptor activation and suppress the constitutively activated receptor mutants. J Biol Chem 2012; 287:34514-32. [PMID: 22904318 DOI: 10.1074/jbc.m112.355032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The exoloops of glycoprotein hormone receptors (GpHRs) transduce the signal generated by the ligand-ectodomain interactions to the transmembrane helices either through direct hormonal contact and/or by modulating the interdomain interactions between the hinge region (HinR) and the transmembrane domain (TMD). The ligand-induced conformational alterations in the HinRs and the interhelical loops of luteinizing hormone receptor/follicle stimulating hormone receptor/thyroid stimulating hormone receptor were mapped using exoloop-specific antibodies generated against a mini-TMD protein designed to mimic the native exoloop conformations that were created by joining the thyroid stimulating hormone receptor exoloops constrained through helical tethers and library-derived linkers. The antibody against the mini-TMD specifically recognized all three GpHRs and inhibited the basal and hormone-stimulated cAMP production without affecting hormone binding. Interestingly, binding of the antibody to all three receptors was abolished by prior incubation of the receptors with the respective hormones, suggesting that the exoloops are buried in the hormone-receptor complexes. The antibody also suppressed the high basal activities of gain-of-function mutations in the HinRs, exoloops, and TMDs such as those involved in precocious puberty and thyroid toxic adenomas. Using the antibody and point/deletion/chimeric receptor mutants, we demonstrate that changes in the HinR-exoloop interactions play an important role in receptor activation. Computational analysis suggests that the mini-TMD antibodies act by conformationally locking the transmembrane helices by means of restraining the exoloops and the juxta-membrane regions. Using GpHRs as a model, we describe a novel computational approach of generating soluble TMD mimics that can be used to explain the role of exoloops during receptor activation and their interplay with TMDs.
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Affiliation(s)
- Ritankar Majumdar
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
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Majumdar R, Dighe RR. The hinge region of human thyroid-stimulating hormone (TSH) receptor operates as a tunable switch between hormone binding and receptor activation. PLoS One 2012; 7:e40291. [PMID: 22792265 PMCID: PMC3391290 DOI: 10.1371/journal.pone.0040291] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Accepted: 06/05/2012] [Indexed: 01/12/2023] Open
Abstract
The mechanism by which the hinge regions of glycoprotein hormone receptors couple hormone binding to activation of downstream effecters is not clearly understood. In the present study, agonistic (311.62) and antagonistic (311.87) monoclonal antibodies (MAbs) directed against the TSH receptor extracellular domain were used to elucidate role of the hinge region in receptor activation. MAb 311.62 which identifies the LRR/Cb-2 junction (aa 265–275), increased the affinity of TSHR for the hormone while concomitantly decreasing its efficacy, whereas MAb 311.87 recognizing LRR 7–9 (aa 201–259) acted as a non-competitive inhibitor of Thyroid stimulating hormone (TSH) binding. Binding of MAbs was sensitive to the conformational changes caused by the activating and inactivating mutations and exhibited differential effects on hormone binding and response of these mutants. By studying the effects of these MAbs on truncation and chimeric mutants of thyroid stimulating hormone receptor (TSHR), this study confirms the tethered inverse agonistic role played by the hinge region and maps the interactions between TSHR hinge region and exoloops responsible for maintenance of the receptor in its basal state. Mechanistic studies on the antibody-receptor interactions suggest that MAb 311.87 is an allosteric insurmountable antagonist and inhibits initiation of the hormone induced conformational changes in the hinge region, whereas MAb 311.62 acts as a partial agonist that recognizes a conformational epitope critical for coupling of hormone binding to receptor activation. The hinge region, probably in close proximity with the α-subunit in the hormone-receptor complex, acts as a tunable switch between hormone binding and receptor activation.
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MESH Headings
- Algorithms
- Allosteric Regulation
- Amino Acid Motifs
- Amino Acid Sequence
- Amino Acid Substitution
- Animals
- Antibodies, Monoclonal, Murine-Derived/immunology
- Antibodies, Monoclonal, Murine-Derived/pharmacology
- Binding, Competitive
- Cattle
- Cell Surface Display Techniques
- Cyclic AMP/metabolism
- Epitope Mapping
- HEK293 Cells
- Humans
- Mutagenesis, Site-Directed
- Peptide Fragments/chemistry
- Peptide Fragments/immunology
- Protein Binding
- Protein Structure, Tertiary
- Receptors, Thyrotropin/chemistry
- Receptors, Thyrotropin/genetics
- Receptors, Thyrotropin/immunology
- Receptors, Thyrotropin/metabolism
- Second Messenger Systems
- Thyrotropin/metabolism
- Thyrotropin/physiology
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Affiliation(s)
- Ritankar Majumdar
- Department of Molecular Reproduction, Development and Genetics,Indian Institute of Science, Bangalore, Karnataka, India
| | - Rajan R. Dighe
- Department of Molecular Reproduction, Development and Genetics,Indian Institute of Science, Bangalore, Karnataka, India
- * E-mail:
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Majumdar R, Railkar R, Dighe RR. Insights into differential modulation of receptor function by hinge region using novel agonistic lutropin receptor and inverse agonistic thyrotropin receptor antibodies. FEBS Lett 2012; 586:810-7. [PMID: 22309849 DOI: 10.1016/j.febslet.2012.01.052] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Revised: 01/23/2012] [Accepted: 01/23/2012] [Indexed: 01/16/2023]
Abstract
We report two antibodies, scFv 13B1 and MAb PD1.37, against the hinge regions of LHR and TSHR, respectively, which have similar epitopes but different effects on receptor function. While neither of them affected hormone binding, with marginal effects on hormone response, scFv 13B1 stimulated LHR in a dose-dependent manner, whereas MAb PD1.37 acted as an inverse agonist of TSHR. Moreover, PD1.37 could decrease the basal activity of hinge region CAMs, but had varied effects on those present in ECLs, whereas 13B1 was refractory to any CAMs in LHR. Using truncation mutants and peptide phage display, we compared the differential roles of the hinge region cysteine box-2/3 as well as the exoloops in the activation of these two homologus receptors.
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Affiliation(s)
- Ritankar Majumdar
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, Karnataka, India
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Tchou J, Satija C, Zhang P, Bi Y, Davuluri R, Chen H, Majumdar R, Mies C, Herlyn M, Pure E. P1-03-09: Significance of FAP, SMA and CD31 Expression in the Stroma of Breast Cancer. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p1-03-09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Breast cancer stroma heterogeneity has been demonstrated in various gene expression profile analyses. Whether there is any association between stroma heterogeneity and the molecular phenotype of breast cancer has yet to be established. Therefore, we performed immunohistochemical analyses (IHC) to evaluate the expression of the following stromal cell markers (fibroblast activation protein (FAP), smooth muscle actin (SMA), and CD31, an endothelial cell marker) in tumor tissues from a contemporary cohort of 52 patients comprising of all four molecular subtypes (luminal A (n=25); luminal B (n=2); Her2-neu (+) (n=5); and basal (n=20)). We hypothesize that stroma heterogeneity as reflected by the proportion of stromal cells staining (+) for FAP and SMA may correlate with their molecular epithelial phenotype. Furthermore, studying the distribution of these stromal cell markers in IHC sections may evaluate their spatial relationship with tumor cells, immune cells, and tumor microvasculature which may have strategic significance within the tumor/microenvironment.
As shown in Table 1, FAP is a more robust stromal cell marker staining 85±14% of stromal cells compared to SMA which stains only 28±29% of stromal cells (p<0.05). However, the distribution of FAP, SMA and microvessel density appears to be similar in all four subtypes. Multivariate analyses to correlate molecular subtype, tumor grade, tumor size, the no. of (+) nodes, and age with the% stromal cells staining (+) for FAP, SMA and CD31 yielded a significant correlation between the intensity of FAP(+) cells with tumor size, tumor grade, and the no. of positive nodes (p=0.00134, 0.0044, and 0.01141 respectively). We conclude that 1) stroma heterogeneity on IHC does not differ significantly across molecular subtypes; 2) FAP is a robust stromal cell marker; and 3) a higher FAP expression intensity on IHC may correlate with poor prognosis. Recent reports on the role of FAP in promoting tumor growth plus the abundance of FAP expression in breast cancer stroma underscore a significant role of FAP in breast cancer.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-03-09.
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Affiliation(s)
- J Tchou
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - C Satija
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - P Zhang
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - Y Bi
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - R Davuluri
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - H Chen
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - R Majumdar
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - C Mies
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - M Herlyn
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
| | - E Pure
- 1Perleman School of Medicine at University of Pennsylvania, Philadelphia, PA; Perleman School of Medicine at University of Pennsylvania; Wistar Institute, Philadelphia
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Balaji B, Banik B, Sasmal PK, Maity B, Majumdar R, Dighe RR, Chakravarty AR. Ferrocene-Conjugated Oxidovanadium(IV) Complexes as Potent Near-IR Light Photocytotoxic Agents. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201100836] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Majumdar R, Railkar R, Dighe RR. Docking and free energy simulations to predict conformational domains involved in hCG-LH receptor interactions using recombinant antibodies. Proteins 2011; 79:3108-22. [PMID: 21989932 DOI: 10.1002/prot.23138] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 07/16/2011] [Accepted: 07/18/2011] [Indexed: 11/05/2022]
Abstract
Single chain fragment variables (ScFvs) have been extensively employed in studying the protein-protein interactions. ScFvs derived from phage display libraries have an additional advantage of being generated against a native antigen, circumventing loss of information on conformational epitopes. In the present study, an attempt has been made to elucidate human chorionic gonadotropin (hCG)-luteinizing hormone (LH) receptor interactions by using a neutral and two inhibitory ScFvs against hCG. The objective was to dock a computationally derived model of these ScFvs onto the crystal structure of hCG and understand the differential roles of the mapped epitopes in hCG-LH receptor interactions. An anti-hCG ScFv, whose epitope was mapped previously using biochemical tools, served as the positive control for assessing the quality of docking analysis. To evaluate the role of specific side chains at the hCG-ScFv interface, binding free energy as well as residue interaction energies of complexes in solution were calculated using molecular mechanics Poisson-Boltzmann/surface area method after performing the molecular dynamic simulations on the selected hCG-ScFv models and validated using biochemical and SPR analysis. The robustness of these calculations was demonstrated by comparing the theoretically determined binding energies with the experimentally obtained kinetic parameters for hCG-ScFv complexes. Superimposition of hCG-ScFv model onto a model of hCG complexed with the 51-266 residues of LH receptor revealed importance of the residues previously thought to be unimportant for hormone binding and response. This analysis provides an alternate tool for understanding the structure-function analysis of ligand-receptor interactions.
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Affiliation(s)
- Ritankar Majumdar
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, Karnataka 560 012, India
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Lahiri D, Majumdar R, Mallick D, Goswami TK, Dighe RR, Chakravarty AR. Remarkable photocytotoxicity in hypoxic HeLa cells by a dipyridophenazine copper(II) Schiff base thiolate. J Inorg Biochem 2011; 105:1086-94. [PMID: 21726772 DOI: 10.1016/j.jinorgbio.2011.05.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 05/12/2011] [Accepted: 05/18/2011] [Indexed: 12/01/2022]
Abstract
Copper(II) complexes [Cu(satp)(L)] (1-3) of a Schiff base thiolate (salicylidene-2-aminothiophenol, H2satp) and phenanthroline bases (L), viz. 1,10-phenanthroline (phen in 1), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq in 2) and dipyrido[3,2-a:2',3'-c]phenazine (dppz in 3), were prepared, characterized and their anaerobic DNA photocleavage activity and hypoxic photocytotoxicity studied. The redox active complexes show the Cu(II)-Cu(I) couple near -0.5 V for 1 and near 0.0 V vs. SCE (saturated calomel electrode) for 2 and 3. The one-electron paramagnetic complexes (~1.85 μB) are avid DNA binders giving Kb values within 1.0×10(5)-8.0×10(5) M(-1). Thermal melting and viscosity data along with molecular docking calculations suggest DNA groove and/or partial intercalative binding of the complexes. The complexes show anaerobic DNA cleavage activity in red light under argon via type-I pathway, while DNA photocleavage in air proceeds via hydroxyl radical pathway. The DFT (density functional theory) calculations reveal a thyil radical pathway for the anaerobic DNA photocleavage activity and suggest the possibility of generation of a transient copper(I) species due to bond breakage between the copper and sulfur to generate the thyil radical. An oxidation of the copper(I) species is likely by oxygen in an aerobic medium or by the buffer medium in an anaerobic condition. Complex 3 exhibits significant photocytotoxicity in HeLa cells (IC50=8.3(±1.0) μM) in visible light, while showing lower dark toxicity (IC50=17.2(±1.0) μM). A significant reduction in the dark toxicity is observed under hypoxic cellular conditions (IC50=30.0(±1.0) μM in dark), while retaining its photocytotoxicity (IC50=8.0(±1.0) μM).
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Affiliation(s)
- Debojyoti Lahiri
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Sir C. V. Raman Avenue, Bangalore 560012, India
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Saha S, Mallick D, Majumdar R, Roy M, Dighe RR, Jemmis ED, Chakravarty AR. Structure−Activity Relationship of Photocytotoxic Iron(III) Complexes of Modified Dipyridophenazine Ligands. Inorg Chem 2011; 50:2975-87. [DOI: 10.1021/ic1024229] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Banik B, Sasmal PK, Roy S, Majumdar R, Dighe RR, Chakravarty AR. Terpyridine Oxovanadium(IV) Complexes of Phenanthroline Bases for Cellular Imaging and Photocytotoxicity in HeLa Cells. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201001097] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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24
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Roy S, Roy S, Saha S, Majumdar R, Dighe RR, Jemmis ED, Chakravarty AR. Cobalt(ii) complexes of terpyridine bases as photochemotherapeutic agents showing cellular uptake and photocytotoxicity in visible light. Dalton Trans 2011; 40:1233-42. [DOI: 10.1039/c0dt00223b] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Roy S, Saha S, Majumdar R, Dighe RR, Chakravarty AR. Photo-activated cytotoxicity of a pyrenyl-terpyridine copper(II) complex in HeLa cells. Polyhedron 2010. [DOI: 10.1016/j.poly.2010.09.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Saha S, Majumdar R, Dighe RR, Chakravarty AR. Enhanced photodynamic effect of cobalt(III) dipyridophenazine complex on thyrotropin receptor expressing HEK293 cells. Metallomics 2010; 2:754-65. [PMID: 21072367 DOI: 10.1039/c0mt00028k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Ternary cobalt(III) complexes [CoL(B)] (1-3) of a trianionic tetradentate phenolate-based ligand (L) and phenanthroline bases (B), viz. 1,10-phenanthroline (phen in 1), dipyridoquinoxaline (dpq in 2) and dipyridophenazine (dppz in 3) are synthesized, characterized from X-ray crystallographic, analytical and spectral techniques, and their utility in photodynamic therapy (PDT) of thyroid diseases caused by TSH receptor dysfunction is probed. The complexes display a visible spectral band within the PDT spectral window at ~690 nm. Photodynamic potential was estimated through DNA cleavage activity of the dpq and dppz complexes in UV-A light of 365 nm and red light of 676 nm. The reactions proceed via the hydroxyl radical pathway. The complexes retain their DNA photocleavage activity in red light under anaerobic conditions, a situation normally prevails in hypoxic tumor core. Investigation into the photocytotoxic potential of these complexes showed that the dppz complex 3 is approximately 4-fold more active in the HEK293 cells expressing human thyrotropin receptor (HEK293-hTSHR) than in the parental cell line and has an insignificant effect on an unrelated human cervical carcinoma cell line (HeLa). Photoexcitation of complex 3 in HEK293-hTSHR cells leads to damage hTSHR as evidenced from the decrease in cAMP formation both in absence and presence of hTSH and decrease in the TSHR immunofluorescence with a concomitant cytoplasmic translocation of the membrane protein, cadherin. The involvement of hTSHR is evidenced from the ability of complex 3 to bind to the extracellular domain of hTSHR (hTSHR-ECD) with a K(d) value of 81 nM and from the photocleavage of hTSHR-ECD.
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Affiliation(s)
- Sounik Saha
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, Karnataka, India
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Prasad P, Sasmal PK, Majumdar R, Dighe RR, Chakravarty AR. Photocytotoxicity and near-IR light DNA cleavage activity of oxovanadium(IV) Schiff base complexes having phenanthroline bases. Inorganica Chim Acta 2010. [DOI: 10.1016/j.ica.2010.03.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Roy S, Saha S, Majumdar R, Dighe RR, Chakravarty AR. DNA photocleavage and anticancer activity of terpyridine copper(II) complexes having phenanthroline bases. Polyhedron 2010. [DOI: 10.1016/j.poly.2010.06.028] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Lahiri D, Majumdar R, Patra AK, Chakravarty AR. Anaerobic DNA cleavage in red light by dicopper(II) complexes on disulphide bond activation. J CHEM SCI 2010. [DOI: 10.1007/s12039-010-0037-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Maity B, Roy M, Banik B, Majumdar R, Dighe RR, Chakravarty AR. Ferrocene-Promoted Photoactivated DNA Cleavage and Anticancer Activity of Terpyridyl Copper(II) Phenanthroline Complexes. Organometallics 2010. [DOI: 10.1021/om100524x] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
| | - Mithun Roy
- Department of Inorganic and Physical Chemistry
| | | | - Ritankar Majumdar
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
| | - Rajan R. Dighe
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
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Majumdar R, Alexander KS, Riga AT. Physical characterization of polyethylene glycols by thermal analytical technique and the effect of humidity and molecular weight. Pharmazie 2010; 65:343-347. [PMID: 20503926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Polyethylene glycols (PEGs) are well known as excipients in tablet dosage formulations. PEGs are generally known to be inert and have very few interactions with other components in the solid dosage forms. However, the physical nature of PEGs and how they affect the disintegration of tablets is not very well understood for the different molecular weights of PEGs. The knowledge of the effect of molecular weight of PEGs on their physical properties and the effect of humidity on the physical properties of PEGs are important parameters for the choice of a PEG to be acceptable as an excipient in pharmaceutical formulations. This study was done to determine the precision of the DSC physical properties for a wide range of PEGs with varying molecular weights from 194 to 23000 daltons. Nine different molecular weights of PEGs were examined in a DSC controlled Heat-Cool-Heat-Cool-Heat (HCHCH) cycle and the observed reproducible values of melting temperature, heat of fusion, crystallization temperature and the heat of crystallization were compared with values obtained from the literature and the observed percent crystallinity was again cross-checked by X-ray Diffraction (XRD) studies. The comparison values indicated acceptable precision. This study was also done to check the effect of humidity on the DSC physical properties for the entire range of PEGs. The results indicated that humidity probably has a higher effect on the physical properties of the low molecular weight PEGs as compared to the high molecular weight PEGs.
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Affiliation(s)
- R Majumdar
- Division of Industrial Pharmacy, College of Pharmacy, The University of Toledo, OH 43606, USA.
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Hussain A, Lahiri D, Ameerunisha Begum MS, Saha S, Majumdar R, Dighe RR, Chakravarty AR. Photocytotoxic Lanthanum(III) and Gadolinium(III) Complexes of Phenanthroline Bases Showing Light-Induced DNA Cleavage Activity. Inorg Chem 2010; 49:4036-45. [DOI: 10.1021/ic901791f] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
| | | | | | - Sounik Saha
- Department of Inorganic and Physical Chemistry
| | | | - Rajan R. Dighe
- Department of Molecular Reproduction, Development, and Genetics
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Sasmal PK, Majumdar R, Dighe RR, Chakravarty AR. Photocytotoxicity and DNA cleavage activity of l-arg and l-lys Schiff base oxovanadium(iv) complexes having phenanthroline bases. Dalton Trans 2010; 39:7104-13. [DOI: 10.1039/c001867h] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Lahiri D, Roy S, Saha S, Majumdar R, Dighe RR, Chakravarty AR. Anaerobic DNA cleavage activity in red light and photocytotoxicity of (pyridine-2-thiol)cobalt(iii) complexes of phenanthroline bases. Dalton Trans 2010; 39:1807-16. [DOI: 10.1039/b917860k] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Sasmal PK, Saha S, Majumdar R, De S, Dighe RR, Chakravarty AR. Oxovanadium(iv) complexes of phenanthroline bases: the dipyridophenazine complex as a near-IR photocytotoxic agent. Dalton Trans 2010; 39:2147-58. [DOI: 10.1039/b917265c] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Sasmal PK, Saha S, Majumdar R, Dighe RR, Chakravarty AR. Photocytotoxic Oxovanadium(IV) Complexes Showing Light-Induced DNA and Protein Cleavage Activity. Inorg Chem 2009; 49:849-59. [DOI: 10.1021/ic900701s] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Pijus K. Sasmal
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Sounik Saha
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Ritankar Majumdar
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
| | - Rajan R. Dighe
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
| | - Akhil R. Chakravarty
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
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Roy S, Saha S, Majumdar R, Dighe RR, Chakravarty AR. Photocytotoxic 3d-Metal Scorpionates with a 1,8-Naphthalimide Chromophore Showing Photoinduced DNA and Protein Cleavage Activity. Inorg Chem 2009; 48:9501-9. [DOI: 10.1021/ic9015355] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sovan Roy
- Department of Inorganic and Physical Chemistry
- Department of Molecular Reproduction, Development and Genetics
- Indian Institute of Science, Bangalore 560012, India
| | - Sounik Saha
- Department of Inorganic and Physical Chemistry
- Department of Molecular Reproduction, Development and Genetics
- Indian Institute of Science, Bangalore 560012, India
| | - Ritankar Majumdar
- Department of Inorganic and Physical Chemistry
- Department of Molecular Reproduction, Development and Genetics
- Indian Institute of Science, Bangalore 560012, India
| | - Rajan R. Dighe
- Department of Inorganic and Physical Chemistry
- Department of Molecular Reproduction, Development and Genetics
- Indian Institute of Science, Bangalore 560012, India
| | - Akhil R. Chakravarty
- Department of Inorganic and Physical Chemistry
- Department of Molecular Reproduction, Development and Genetics
- Indian Institute of Science, Bangalore 560012, India
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Saha S, Majumdar R, Roy M, Dighe RR, Chakravarty AR. An Iron Complex of Dipyridophenazine as a Potent Photocytotoxic Agent in Visible Light. Inorg Chem 2009; 48:2652-63. [DOI: 10.1021/ic8022612] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Sounik Saha
- Department of Inorganic and Physical Chemistry and Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
| | - Ritankar Majumdar
- Department of Inorganic and Physical Chemistry and Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
| | - Mithun Roy
- Department of Inorganic and Physical Chemistry and Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
| | - Rajan R. Dighe
- Department of Inorganic and Physical Chemistry and Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
| | - Akhil R. Chakravarty
- Department of Inorganic and Physical Chemistry and Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560012, India
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Sasmal PK, Saha S, Majumdar R, Dighe RR, Chakravarty AR. Oxovanadium(iv)-based near-IR PDT agents: design to biological evaluation. Chem Commun (Camb) 2009:1703-5. [DOI: 10.1039/b822229k] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Dewanjee S, Kundu M, Maiti A, Majumdar R, Majumdar A, Mandel SC. In Vitro Evaluation of Antimicrobial Activity of Crude Extract from Plants Diospyros peregrina, Coccinia grandis and Swietenia macrophylla. TROP J PHARM RES 2007. [DOI: 10.4314/tjpr.v6i3.14658] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Majumdar R, Rehana Z, Jumah MA, Fetaini N. Spinal Muscular Atrophy Carrier Screening by Multiplex Polymerase Chain Reaction using Dried Blood Spot on Filter Paper. Ann Hum Genet 2005. [DOI: 10.1046/j.1469-1809.2004.00149.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Majumdar R, Rehana Z, Al Jumah M, Fetaini N. Spinal muscular atrophy carrier screening by multiplex polymerase chain reaction using dried blood spot on filter paper. Ann Hum Genet 2005; 69:216-21. [PMID: 15720302 DOI: 10.1046/j.1529-8817.2004.00149.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Spinal muscular atrophy (SMA) is a common, often fetal, autosomal recessively inherited disease leading to progressive muscle wasting and paralysis as a result of degeneration of anterior horn cells of the spinal cord. The SMA-determining gene, called the survival of motor neuron gene (SMN), is present on 5q13 in two nearly identical copies, telomeric SMN (SMN1) and centromeric SMN (SMN2). It has been established that SMA is caused by mutations in SMN1 whereas homozygous deletion of SMN2 has apparently no pathological consequences. The aim of this study is to develop an easy and inexpensive method for the isolation of high-quality template DNA from blood samples for SMA carrier screening by multiplex polymerase chain reaction. We have developed a protocol that optimizes detection of the SMN1 copy number in the human genome, producing a specific and sensitive assay using DNA extracted from a dried blood spot on IsoCode paper.
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Affiliation(s)
- R Majumdar
- Neurogenetics Laboratory, Department of Medicine, King Fahad National Guard Hospital, PO Box 22490, Riyadh 11426, Saudi Arabia.
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Al Jumah M, Majumdar R, Al Rajeh S, Awada A, Al Zaben A, Al Traif I, Al Jumah AR, Rehana Z. A clinical and genetic study of 56 Saudi Wilson disease patients: identification of Saudi-specific mutations. Eur J Neurol 2004; 11:121-4. [PMID: 14748773 DOI: 10.1046/j.1351-5101.2003.00729.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Wilson disease (WD) is a hereditary disorder, with recessive transmission and genetic heterogeneity. Several mutations of ATP7B, the gene underlying WD, were reported in many ethnic groups. In this study, mutation screening in ATP7B of 56 Saudi Arabian WD patients was undertaken. The clinical data of all patients were recorded. The entire ATP7B coding sequence, including intron-exon boundaries were screened for mutation by the polymerase chain reaction (PCR)-based mutation detection technique and DNA sequencing. Thirty-nine patients were symptomatic at presentation and 17 subjects were pre-symptomatic siblings of affected patients. Fourteen patients had neurological, 11 patients had mixed (hepatic and neurological), and 14 patients had hepatic presentations. Family history suggestive of WD was present in 72% of cases and 68% had consanguineous parents. Genetic analysis showed disease-causing mutations in three exons (exons 8, 19 and 21) of the ATP7B gene in 28 patients (50%). Mutations in exons 21 (18 cases) and 19 (one case) were unique for Saudis. This large series of Saudi patients with WD has shown wide variability in the genomic substrate of WD. There is no correlation between genotype and clinical presentation.
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Affiliation(s)
- M Al Jumah
- Section of Neurology, Department of Medicine, King Fahad National Guard Hospital, Riyadh, Saudi Arabia.
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Majumdar R, Al Jumah M, Fraser M. 4193delC, a common mutation causing Wilson's disease in Saudi Arabia: rapid molecular screening of patients and carriers. Mol Pathol 2003; 56:302-4. [PMID: 14514926 PMCID: PMC1187343 DOI: 10.1136/mp.56.5.302] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2003] [Indexed: 11/04/2022]
Abstract
BACKGROUND In patients with Wilson's disease (WD), an autosomal recessive disorder, toxic accumulation of copper results in fatal liver disease and irreversible neuronal degeneration. ATP7B, the gene mutated in WD, contains 21 exons and encodes a copper transporting ATPase. A novel disease causing mutation (4193delC) in exon 21 of the ATP7B gene has previously been detected by heteroduplex analysis and DNA sequencing. AIMS To screen for the above mutation in patients with WD and carriers using an amplification refractory mutation system (ARMS). METHODS ARMS was used to screen for the 4193delC mutation in 30 patients with WD and their relatives. RESULTS A homozygous mutation was detected in 16 of 30 patients with WD. CONCLUSIONS This polymerase chain reaction based method, which has been known for years, is a simple, inexpensive, and rapid method for screening common and specific mutations in patients with WD and carriers.
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Affiliation(s)
- R Majumdar
- Department of Medicine, King Fahad National Guard Hospital, Riyadh 11426, Saudi Arabia.
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Bhattacharyya D, Majumdar R. Structural basis of DNA flexibility. Indian J Biochem Biophys 2001; 38:16-9. [PMID: 11563325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
It has been recently shown by us, on the basis of crystal structure database that the flexibility of B-DNA double helices depends significantly on their base sequence. Our model building studies further indicated that the existence of bifurcated cross-strand hydrogen bonds between successive base pairs is possibly the main factor behind the sequence directed DNA flexibility. These cross-strand hydrogen bonds are, of course, weaker than the usual Watson-Crick hydrogen bonds and their bond geometry is characterized by relatively larger bond lengths and smaller bond angles. We have tried to improve our model structures by incorporating non-planarity of the amino groups in DNA bases due to the presence of lone pair electrons at the nitrogen atoms. Energy minimization studies have been carried out by using different quantum chemical methods, whereby it is found that in all cases of N-H....O type cross-strand hydrogen bonds, the bond geometry improves significantly. In the cases of N-H....N type hydrogen bonds, however, no such consistent improvements can be noticed. Perhaps the true picture would emerge only if all the other interactions present in the DNA macromolecule could be appropriately taken into account.
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Affiliation(s)
- D Bhattacharyya
- Biophysics Division, Saha Institute of Nuclear Physics, 37 Belgachia Road, Calcutta 700037, India
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Abstract
Based on worm like chain model, DNA structural parameters--tilt, roll and rise, derived from crystallographic database have been used to determine the flexibility of DNA that regulates the nucleosomal translational positioning. Theoretically derived data has been compared to the experimental values available in loshikhes and Trifonov's database. The methodology has been extended to determine the flexibility of 18S rRNA genome in eukarya, where yeast shows a distinct difference when compared with mammals like human, mouse and rabbit.
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Affiliation(s)
- S Kundu
- Department of Biophysics, Molecular Biology & Genetics, University College of Science, Calcutta, India
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Majumdar R, Al Jumah M, Al Rajeh S, Fraser M, Al Zaben A, Awada A, Al Traif I, Paterson M. A novel deletion mutation within the carboxyl terminus of the copper-transporting ATPase gene causes Wilson disease. J Neurol Sci 2000; 179:140-3. [PMID: 11054498 DOI: 10.1016/s0022-510x(00)00399-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In patients with Wilson disease (WD), an autosomal recessive disorder, toxic accumulation of copper results in fatal liver disease and irreversible neuronal degeneration. ATP7B, the gene mutated in WD, contains 21 exons and encodes a copper-transporting ATPase. In this study, all exons of the ATP7B gene of nine WD patients were screened for alterations by conventional mutation detection enhancement (MDE) heteroduplex analysis, followed by direct sequencing of the regions that showed heteroduplex formation. For the first time, a novel deletion mutation (4193delC) in exon 21, causing a frameshift leading to premature truncation of the protein was detected in four of nine patients. The 4193delC removes several signals within the carboxyl terminal domain that may disrupt trafficking of ATP7B protein through trans-Golgi network at the cellular level.
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Affiliation(s)
- R Majumdar
- Neurogenetics Laboratory, Department of Medicine (Mail Code 1443), King Fahad National Guard Hospital, 11426, Riyadh, Saudi Arabia.
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Abstract
It has been suggested that removal of a laryngeal mask airway with the cuff inflated may remove more secretions than with the cuff deflated. We performed a study to determine whether this suggestion is correct. Patients were randomly allocated to removal of the laryngeal mask airway with the cuff deflated (n = 75) or inflated (n = 74). The laryngeal mask airways were weighed before insertion and after removal, the difference in these two weights being taken to be the mass of secretions adherent to the airways on removal. The mean (SD) increase in laryngeal mask airway weight was 2.45 (1.47) g with the cuff deflated and 3.03 (1.76) g with the cuff inflated (p = 0.03). We conclude that removal of the laryngeal mask airway with the cuff inflated removes approximately 0.5 g more secretions than with the cuff deflated.
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Affiliation(s)
- C D Deakin
- Consultant Anasthetist; Specialist Registrar; Senior House Officer, Department of Anasthetics, Southampton General Hospital, Tremona Road, Southampton SO16 6YD, UK
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Al Rajeh S, Majumdar R, Awada A, Al Jumah M. Application of DNA-based tests for diagnosis of spinal muscular atrophy in Saudi Arabia. East Mediterr Health J 1999. [DOI: 10.26719/1999.5.6.1225] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We examined the deletion of the survival motor neuron [SMN] and neuronal apoptosis inhibitory protein [NAIP]genes in patients with spinal muscular atrophy [SMA] using polymerase chain reaction followed by restriction site assay methods. The study included 16 Saudi patients [9 SMA type I and 7 SMA type II]and 6 healthy Saudi volunteers. The homozygous deletions of exons 7 and 8 of the telomeric SMN gene, and exon 5 of the NAIP gene were found in all SMA type I patients. Exons 7 and 8 of telomeric SMN were deleted in all SMA type II patients. However, exon 5 of NAIP was deleted in three of the seven cases. All control volunteers and all family members of the patients had normal SMN and NAIP. The incidence of NAIP deletion was higher in the more severe SMA cases and the dual deletion of the SMN and NAIP genes was more common in Saudi SMA type I patients compared with patients of other ethnic groups
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