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Giometti I, Veras A, Pacagnelli F, Schaffer L, Oliveira M, Nespolo R, Santos A, Souza F, Castilho C, Favareto AP, Mendes L, Teixeira G. P–073 High-intensity interval training modulates the effects of hypertension on inflammatory mediators in testis in adult spontaneously hypertensive rats. Hum Reprod 2021. [DOI: 10.1093/humrep/deab130.072] [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: 11/13/2022] Open
Abstract
Abstract
Study question
Is the high-intensity interval training (HIIT) able to prevent the increase of the inflammatory proteins in the testis of spontaneously hypertensive rats (SHR)?
Summary answer
HIIT for 8 weeks inhibits the increase of the tumor necrosis factor alpha (TNFα) and the interleukin 6 (IL6) in the testis of SHR.
What is known already
Hypertension increases the inflammatory cytokines of the cardiovascular system, causing damage in the microcirculation and in the testes. Hypertension is a cause of low fertility in men and exercises are indicated to decrease blood pressure and improve overall health. HIIT is characterized by short periods of exercise, with an intensity equal to or greater than the anaerobic threshold, separated by recovery periods. HIIT can be indicated for cardiac patients, as this type of training improves the cardiac autonomic nervous system and lipemic control in both hypertensive and normotensive individuals.
Study design, size, duration
Male Wistar-Kyoto rats without hypertension and SHRs were divided into 3 groups (n = 4): WKY (Wistar-Kyoto); SHR; and SHR-HIIT (SHRs that performed HIIT). The HIIT was realized in treadmill for 5 days/week for 8 weeks. HIIT started with 5 times of 4 minutes of 100% of the maximum exhaust speed, with active rest intervals of 3 minutes at 60%. There was an increase of once every week until reaching 7 times each session.
Participants/materials, setting, methods
Samples from testicles were used for immunostainig IL6 and TNFα. After the blocking, the sections were subjected to reaction of specific antibodies IL6 (1:50, E–4, sc–28343) and TNFα (1:50, 52B83, sc–257) at 4ºC overnight, and with secondary antibodies m-IgGK (1:200, IgG-HRP, sc–516) at room temperature for 2 hours. Diaminobenzidine (1:50) was used against Harris stained with Hematoxylin and evaluated in the photomicroscope. Data were analyzed by One-Way ANOVA followed by Tukey post test (P < 0.05).
Main results and the role of chance
The immunostainig of IL6 was higher in SHR (10.23 ± 0.47) than in SHR-HIIT (8.69 ± .44) group (P = 0,0237). From the same perspective, immunoexpression of TNFα was higher in SHR (10.10 ± 0.42) than WKY (8.24 ± 0.24) and SHR-HIIT (7.82 ± 0.39) groups (P = 0.0018).
Limitations, reasons for caution
As a limitation of the study, we have no measurement of fertility parameters to affirm that the HIIT improve the fertility because of the reduction of inflammatory mediators.
Wider implications of the findings: The hypertension drugs have a negative effect on fertility. HIIT can be suggested as a treatment for hypertension as an alternative to medication, since HIIT can inhibit the increase of the inflammatory mediators in testis and its consequences to the reproduction. Financial support by São Paulo Research foundation, FAPESP (2018/22682–0).
Trial registration number
2018/22682–0
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Affiliation(s)
- I Giometti
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - A Veras
- Universidade Estadual Paulista - UNESP, Departamento de Educação Física, Presidente Prudente - SP, Brazil
| | - F Pacagnelli
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - L Schaffer
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - M Oliveira
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - R Nespolo
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - A Santos
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - F Souza
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - C Castilho
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - A P Favareto
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - L Mendes
- Universidade do Oeste Paulista - UNOESTE, Programa de Pós-graduação em Ciência Animal, Presidente Prudente - SP, Brazil
| | - G Teixeira
- Universidade Estadual Paulista - UNESP, Departamento de Educação Física, Presidente Prudente - SP, Brazil
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Braun H, Schaffer L, Cole E, Risk B, Kim H, Feldman R. 367 Entropion repair outcomes in ocular cicatricial pemphigoid versus other cicatricial etiologies: A retrospective study. J Invest Dermatol 2021. [DOI: 10.1016/j.jid.2021.02.389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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3
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Shi Z, Zhang Z, Schaffer L, Huang Z, Fu L, Head S, Gaasterland T, Wang X, Li X. Dynamic transcriptome landscape in the song nucleus HVC between juvenile and adult zebra finches. Adv Genet (Hoboken) 2021; 2:e10035. [PMID: 36618441 PMCID: PMC9744550 DOI: 10.1002/ggn2.10035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 09/25/2020] [Accepted: 10/15/2020] [Indexed: 01/11/2023]
Abstract
Male juvenile zebra finches learn to sing by imitating songs of adult males early in life. The development of the song control circuit and song learning and maturation are highly intertwined processes, involving gene expression, neurogenesis, circuit formation, synaptic modification, and sensory-motor learning. To better understand the genetic and genomic mechanisms underlying these events, we used RNA-Seq to examine genome-wide transcriptomes in the song control nucleus HVC of male juvenile (45 d) and adult (100 d) zebra finches. We report that gene groups related to axon guidance, RNA processing, lipid metabolism, and mitochondrial functions show enriched expression in juvenile HVC compared to the rest of the brain. As juveniles mature into adulthood, massive gene expression changes occur. Expression of genes related to amino acid metabolism, cell cycle, and mitochondrial function is reduced, accompanied by increased and enriched expression of genes with synaptic functions, including genes related to G-protein signaling, neurotransmitter receptors, transport of small molecules, and potassium channels. Unexpectedly, a group of genes with immune system functions is also developmentally regulated, suggesting potential roles in the development and functions of HVC. These data will serve as a rich resource for investigations into the development and function of a neural circuit that controls vocal behavior.
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Affiliation(s)
- Zhimin Shi
- Neuroscience Center of ExcellenceLouisiana State University School of MedicineNew OrleansLouisianaUSA
| | - Zeyu Zhang
- Key Laboratory of Genetic Network BiologyInstitute of Genetics and Developmental Biology, Chinese Academy of SciencesBeijingChina,University of Chinese Academy of SciencesBeijingChina
| | | | - Zhi Huang
- Neuroscience Center of ExcellenceLouisiana State University School of MedicineNew OrleansLouisianaUSA
| | - Lijuan Fu
- Neuroscience Center of ExcellenceLouisiana State University School of MedicineNew OrleansLouisianaUSA,Present address:
California Medical Innovations InstituteSan DiegoCaliforniaUSA
| | - Steven Head
- Scripps Research InstituteLa JollaCaliforniaUSA
| | - Terry Gaasterland
- Scripps Research InstituteLa JollaCaliforniaUSA,University of California at San DiegoLa JollaCaliforniaUSA
| | - Xiu‐Jie Wang
- Key Laboratory of Genetic Network BiologyInstitute of Genetics and Developmental Biology, Chinese Academy of SciencesBeijingChina,University of Chinese Academy of SciencesBeijingChina
| | - XiaoChing Li
- Neuroscience Center of ExcellenceLouisiana State University School of MedicineNew OrleansLouisianaUSA
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Buzby JS, Williams SA, Schaffer L, Head SR, Nugent DJ. Allele-specific wild-type TP53 expression in the unaffected carrier parent of children with Li-Fraumeni syndrome. Cancer Genet 2017; 211:9-17. [PMID: 28279309 DOI: 10.1016/j.cancergen.2017.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 12/14/2016] [Accepted: 01/06/2017] [Indexed: 01/01/2023]
Abstract
Li-Fraumeni syndrome (LFS) is an autosomal dominant disorder where an oncogenic TP53 germline mutation is passed from parent to child. Tumor protein p53 is a key tumor suppressor regulating cell cycle arrest in response to DNA damage. Paradoxically, some mutant TP53 carriers remain unaffected, while their children develop cancer within the first few years of life. To address this paradox, response to UV stress was compared in dermal fibroblasts (dFb) from an affected LFS patient vs. their unaffected carrier parent. UV induction of CDKN1A/p21, a regulatory target of p53, in LFS patient dFb was significantly reduced compared to the unaffected parent. UV exposure also induced significantly greater p53[Ser15]-phosphorylation in LFS patient dFb, a reported property of some mutant p53 variants. Taken together, these results suggested that unaffected parental dFb may express an increased proportion of wild-type vs. mutant p53. Indeed, a significantly increased ratio of wild-type to mutant TP53 allele-specific expression in the unaffected parent dFb was confirmed by RT-PCR-RFLP and RNA-seq analysis. Hence, allele-specific expression of wild-type TP53 may allow an unaffected parent to mount a response to genotoxic stress more characteristic of homozygous wild-type TP53 individuals than their affected offspring, providing protection from the oncogenesis associated with LFS.
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Affiliation(s)
- Jeffrey S Buzby
- Hematology Research and Advanced Diagnostics Laboratories, CHOC Children's Hospital of Orange County, Orange, CA, USA.
| | - Shirley A Williams
- Hematology Research and Advanced Diagnostics Laboratories, CHOC Children's Hospital of Orange County, Orange, CA, USA
| | - Lana Schaffer
- Next Generation Sequencing and Microarray Core Facility, The Scripps Research Institute, La Jolla, CA, USA
| | - Steven R Head
- Next Generation Sequencing and Microarray Core Facility, The Scripps Research Institute, La Jolla, CA, USA
| | - Diane J Nugent
- Hematology Research and Advanced Diagnostics Laboratories, CHOC Children's Hospital of Orange County, Orange, CA, USA; Division of Hematology, CHOC Children's Hospital of Orange County, Orange, CA, USA; Division of Pediatric Hematology, School of Medicine, University of California at Irvine, Orange, CA, USA
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Freidlin PJ, Nissan I, Luria A, Goldblatt D, Schaffer L, Kaidar-Shwartz H, Chemtob D, Dveyrin Z, Head SR, Rorman E. Structure and variation of CRISPR and CRISPR-flanking regions in deleted-direct repeat region Mycobacterium tuberculosis complex strains. BMC Genomics 2017; 18:168. [PMID: 28201993 PMCID: PMC5310062 DOI: 10.1186/s12864-017-3560-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 02/07/2017] [Indexed: 12/16/2022] Open
Abstract
Background CRISPR and CRISPR-flanking genomic regions are important for molecular epidemiology of Mycobacterium tuberculosis complex (MTBC) strains, and potentially for adaptive immunity to phage and plasmid DNA, and endogenous roles in the bacterium. Genotyping in the Israel National Mycobacterium Reference Center Tel-Aviv of over 1500 MTBC strains from 2008–2013 showed three strains with validated negative 43-spacer spoligotypes, that is, with putatively deleted direct repeat regions (deleted-DR/CRISPR regions). Two isolates of each of three negative spoligotype MTBC (a total of 6 isolates) were subjected to Next Generation Sequencing (NGS). As positive controls, NGS was performed for three intact-DR isolates belonging to T3_Eth, the largest multiple-drug-resistant (MDR)-containing African-origin cluster in Israel. Other controls consisted of NGS reads and complete whole genome sequences from GenBank for 20 intact-DR MTBC and for 1 deleted-DR MTBC strain recognized as CAS by its defining RD deletion. Results NGS reads from negative spoligotype MTBC mapped to reference H37Rv NC_000962.3 suggested that the DR/CRISPR regions were completely deleted except for retention of the middle IS6110 mobile element. Clonally specific deletion of CRISPR-flanking genes also was observed, including deletion of at least cas2 and cas1 genes. Genomic RD deletions defined lineages corresponding to the major spoligotype families Beijing, EAI, and Haarlem, consistent with 24 loci MIRU-VNTR profiles. Analysis of NGS reads, and analysis of contigs obtained by manual PCR confirmed that all 43 gold standard DR/CRISPR spacers were missing in the deleted-DR genomes. Conclusions Although many negative spoligotype strains are recorded as spoligotype-international-type (SIT) 2669 in the SITVIT international database, this is the first time to our knowledge that it has been shown that negative spoligotype strains are found in at least 4 different 24 loci MIRU-VNTR and RD deletion families. We report for the first time negative spoligotype-associated total loss of CRISPR region spacers and repeats, with accompanying clonally specific loss of flanking genes, including at least CRISPR-associated genes cas2 and cas1. Since cas1 deleted E.coli shows increased sensitivity to DNA damage and impaired chromosomal segregation, we discussed the possibility of a similar phenotype in the deleted-DR strains and Beijing family strains as both lack the cas1 gene. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3560-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Paul Jeffrey Freidlin
- National Mycobacterium Reference Center, National Public Health Laboratory Tel Aviv, Ministry of Health, Tel Aviv, Israel.
| | - Israel Nissan
- National Mycobacterium Reference Center, National Public Health Laboratory Tel Aviv, Ministry of Health, Tel Aviv, Israel
| | - Anna Luria
- National Mycobacterium Reference Center, National Public Health Laboratory Tel Aviv, Ministry of Health, Tel Aviv, Israel.,current address: Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Drora Goldblatt
- National Mycobacterium Reference Center, National Public Health Laboratory Tel Aviv, Ministry of Health, Tel Aviv, Israel
| | | | - Hasia Kaidar-Shwartz
- National Mycobacterium Reference Center, National Public Health Laboratory Tel Aviv, Ministry of Health, Tel Aviv, Israel
| | - Daniel Chemtob
- Department of Tuberculosis and AIDS, Ministry of Health, Jerusalem, Israel
| | - Zeev Dveyrin
- National Public Health Laboratory Tel Aviv, Ministry of Health, Tel Aviv, Israel
| | | | - Efrat Rorman
- National Public Health Laboratory Tel Aviv, Ministry of Health, Tel Aviv, Israel
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Sweeney JG, Liang J, Giovannone N, Schaffer L, Head SR, Antonopoulos A, Haslam SM, Widlund HR, Dimitroff CJ. “I”-branched Carbohydrates Negatively Regulate Galectin-3-binding and Melanoma Malignancy. The Journal of Immunology 2016. [DOI: 10.4049/jimmunol.196.supp.144.17] [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] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Malignant transformation is often associated with aberrant glycosylation of cell surface proteins. Commonly observed changes in glycan structures include increased presence of sialic acid, altered expression of mucins, and abnormal branching of N-glycans. Increasing evidence supports the idea that the presence of certain glycans correlate with cancer progression by affecting tumor cell invasiveness, ability to bind pro-tumorigenic galectins, and by promoting metastasis to distant organs. Taking this relationship into consideration, we conducted MALDI-TOF mass spectrometry on cell surface glycans as well as glycomic gene profiling from normal human epidermal melanocytes (NHEM) and human metastatic melanoma (MM) cells. We found that a defining feature between NHEMs and MMs was the relative level of “I”-branched and “i”-linear poly-N-acetyllactosamines on N-glycans. While NHEM predominantly expressed “I”-branched structures, MMs expressed “i”-linear modified N-glycans. Furthermore, glycomic gene profiling and confirmatory RT-qPCR data showed that the “I”-branching β1,6 N-acetylglucosaminyltransferase 2, GCNT2, is decreased in MM compared with NHEMs. With regards to its role in malignancy, we found that GCNT2 functioned as a negative regulator of galectin-3 (Gal-3) binding. GCNT2 overexpression in human MM cells inhibited Gal-3 mediated ERK1/2 phosphorylation and significantly reduced primary tumor growth. While GCNT2 knockdown in human MM cells promoted Gal-3 mediated ERK1/2 phosphorylation and significantly enhanced primary tumor growth. These findings highlight new glycobiological insights into melanoma development, implicating GCNT2 as a negative regulator of Gal-3 binding and melanoma malignancy.
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Carney K, Chang YMR, Wilson S, Calnan C, Reddy PS, Chan WY, Gilmartin T, Hernandez G, Schaffer L, Head SR, Morley J, de Mestre A, Affleck K, Garden OA. Regulatory T-cell-intrinsic amphiregulin is dispensable for suppressive function. J Allergy Clin Immunol 2016; 137:1907-1909. [PMID: 27040371 PMCID: PMC4889774 DOI: 10.1016/j.jaci.2016.01.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 12/15/2015] [Accepted: 01/15/2016] [Indexed: 11/26/2022]
Affiliation(s)
- Katharine Carney
- Department of Clinical Science and Services, Immune Regulation Laboratory, Royal Veterinary College, London, United Kingdom
| | - Yu-Mei Ruby Chang
- Research Support Office, Royal Veterinary College, London, United Kingdom
| | - Stephen Wilson
- GlaxoSmithKline, Platform Technology and Science R&D, Stevenage, Hertfordshire, United Kingdom
| | - Clare Calnan
- Department of Clinical Science and Services, Immune Regulation Laboratory, Royal Veterinary College, London, United Kingdom
| | - Pala S Reddy
- Department of Clinical Science and Services, Immune Regulation Laboratory, Royal Veterinary College, London, United Kingdom
| | - Win-Yan Chan
- Department of Clinical Science and Services, Immune Regulation Laboratory, Royal Veterinary College, London, United Kingdom
| | | | | | | | | | - Joanne Morley
- GlaxoSmithKline, Respiratory R&D, Stevenage, Hertfordshire, United Kingdom
| | - Amanda de Mestre
- Department of Comparative Biomedical Sciences, Royal Veterinary College, North Mymms, Hatfield, Hertfordshire, United Kingdom
| | - Karen Affleck
- GlaxoSmithKline, Respiratory R&D, Stevenage, Hertfordshire, United Kingdom
| | - Oliver A Garden
- Department of Clinical Science and Services, Immune Regulation Laboratory, Royal Veterinary College, London, United Kingdom.
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Mamat U, Wilke K, Bramhill D, Schromm AB, Lindner B, Kohl TA, Corchero JL, Villaverde A, Schaffer L, Head SR, Souvignier C, Meredith TC, Woodard RW. Erratum to: Detoxifying Escherichia coli for endotoxin-free production of recombinant proteins. Microb Cell Fact 2015; 14:81. [PMID: 26063122 PMCID: PMC4464710 DOI: 10.1186/s12934-015-0265-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 05/11/2015] [Indexed: 11/30/2022] Open
Affiliation(s)
- Uwe Mamat
- Division of Structural Biochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany.
| | - Kathleen Wilke
- Division of Structural Biochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany
| | - David Bramhill
- Research Corporation Technologies, Inc,, 5210 East Williams Circle, Suite 240, Tucson, AZ, 85711-4410, USA.,Bramhill Biological Consulting, LLC, 8240 East Moonstone Drive, Tucson, AZ, 85750, USA
| | - Andra Beate Schromm
- Division of Immunobiophysics, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany
| | - Buko Lindner
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany
| | - Thomas Andreas Kohl
- Division of Molecular Mycobacteriology, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany
| | - José Luis Corchero
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Bellaterra, 08193, Cerdanyola del Vallès, Spain.,Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193, Cerdanyola del Vallès, Spain.,Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193, Cerdanyola del Vallès, Spain
| | - Antonio Villaverde
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Bellaterra, 08193, Cerdanyola del Vallès, Spain.,Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193, Cerdanyola del Vallès, Spain.,Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193, Cerdanyola del Vallès, Spain
| | - Lana Schaffer
- NGS and Microarray Core Facility, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Steven Robert Head
- NGS and Microarray Core Facility, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Chad Souvignier
- Research Corporation Technologies, Inc,, 5210 East Williams Circle, Suite 240, Tucson, AZ, 85711-4410, USA
| | - Timothy Charles Meredith
- Department of Biochemistry and Molecular Biology, 206 South Frear, Pennsylvania State University, University Park, PA, 16802, USA
| | - Ronald Wesley Woodard
- Department of Medicinal Chemistry, University of Michigan, 428 Church Street, Ann Arbor, MI, 48109-1065, USA
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Sauer K, Conche C, Broaten B, Schaffer L, Rigaud S, Westernberg L, Head S, Siegemund S. IP3 3-kinase B controls hematopoietic stem cell homeostasis and prevents lethal hematopoietic failure in mice (HEM5P.228). The Journal of Immunology 2015. [DOI: 10.4049/jimmunol.194.supp.120.8] [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] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Tight regulation of HSC homeostasis ensures life-long hematopoiesis and prevents blood cancers. The mechanisms balancing HSC quiescence with expansion and differentiation into hematopoietic progenitors are incompletely understood. Here, we identify inositoltrisphosphate (IP3) 3-kinase B (Itpkb) as a novel essential regulator of HSC quiescence and function. Young Itpkb-/- mice accumulated phenotypic HSC which were less quiescent and proliferated more than wildtype controls. Itpkb-/- HSC downregulated quiescence associated mRNAs, but upregulated activation, oxidative metabolism, protein synthesis and lineage associated transcripts. Although they showed no significant homing defects and had normal to elevated viability, Itpkb-/- HSC had a severely reduced competitive long-term repopulating potential. Aging Itpkb-/- mice lost hematopoietic stem and progenitor cells and died with severe anemia. Wildtype HSC normally repopulated Itpkb-/- hosts, indicating a HSC-intrinsic Itpkb requirement. In vitro, Itpkb-/- HSC had reduced cobblestone-area forming cell activity and showed increased stem cell factor activation of the phosphoinositide 3-kinase (PI3K) effector Akt. This was reversed by exogenous provision of the Itpkb product IP4, a known PI3K/Akt antagonist. Itpkb-/- HSC also showed transcriptome changes consistent with hyperactive Akt/mTOR signaling. Thus, we propose that Itpkb ensures HSC quiescence and function in part by limiting cytokine-induced PI3K signaling in HSC.
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Affiliation(s)
| | | | | | | | | | | | - Steven Head
- 1The Scripps Research Institute, La Jolla, CA
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Mamat U, Wilke K, Bramhill D, Schromm AB, Lindner B, Kohl TA, Corchero JL, Villaverde A, Schaffer L, Head SR, Souvignier C, Meredith TC, Woodard RW. Detoxifying Escherichia coli for endotoxin-free production of recombinant proteins. Microb Cell Fact 2015; 14:57. [PMID: 25890161 PMCID: PMC4404585 DOI: 10.1186/s12934-015-0241-5] [Citation(s) in RCA: 154] [Impact Index Per Article: 17.1] [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: 12/23/2014] [Accepted: 04/07/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Lipopolysaccharide (LPS), also referred to as endotoxin, is the major constituent of the outer leaflet of the outer membrane of virtually all Gram-negative bacteria. The lipid A moiety, which anchors the LPS molecule to the outer membrane, acts as a potent agonist for Toll-like receptor 4/myeloid differentiation factor 2-mediated pro-inflammatory activity in mammals and, thus, represents the endotoxic principle of LPS. Recombinant proteins, commonly manufactured in Escherichia coli, are generally contaminated with endotoxin. Removal of bacterial endotoxin from recombinant therapeutic proteins is a challenging and expensive process that has been necessary to ensure the safety of the final product. RESULTS As an alternative strategy for common endotoxin removal methods, we have developed a series of E. coli strains that are able to grow and express recombinant proteins with the endotoxin precursor lipid IVA as the only LPS-related molecule in their outer membranes. Lipid IVA does not trigger an endotoxic response in humans typical of bacterial LPS chemotypes. Hence the engineered cells themselves, and the purified proteins expressed within these cells display extremely low endotoxin levels. CONCLUSIONS This paper describes the preparation and characterization of endotoxin-free E. coli strains, and demonstrates the direct production of recombinant proteins with negligible endotoxin contamination.
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Affiliation(s)
- Uwe Mamat
- Division of Structural Biochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany.
| | - Kathleen Wilke
- Division of Structural Biochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany.
| | - David Bramhill
- Research Corporation Technologies, Inc, 5210 East Williams Circle, Suite 240, Tucson, AZ, 85711-4410, USA. .,Present address: Bramhill Biological Consulting, LLC, 8240 East Moonstone Drive, Tucson, AZ, 85750, USA.
| | - Andra Beate Schromm
- Division of Immunobiophysics, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany.
| | - Buko Lindner
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany.
| | - Thomas Andreas Kohl
- Division of Molecular Mycobacteriology, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany.
| | - José Luis Corchero
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Bellaterra, 08193, Cerdanyola del Vallès, Spain. .,Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193, Cerdanyola del Vallès, Spain. .,Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193, Cerdanyola del Vallès, Spain.
| | - Antonio Villaverde
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Bellaterra, 08193, Cerdanyola del Vallès, Spain. .,Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193, Cerdanyola del Vallès, Spain. .,Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193, Cerdanyola del Vallès, Spain.
| | - Lana Schaffer
- NGS and Microarray Core Facility, The Scripps Research Institute, 10550 North, Pines Road, La Jolla, Torrey, CA, 92037, USA.
| | - Steven Robert Head
- NGS and Microarray Core Facility, The Scripps Research Institute, 10550 North, Pines Road, La Jolla, Torrey, CA, 92037, USA.
| | - Chad Souvignier
- Research Corporation Technologies, Inc, 5210 East Williams Circle, Suite 240, Tucson, AZ, 85711-4410, USA.
| | - Timothy Charles Meredith
- Department of Biochemistry and Molecular Biology, 206 South Frear, Pennsylvania State University, University Park, PA, 16802, USA.
| | - Ronald Wesley Woodard
- Department of Medicinal Chemistry, University of Michigan, 428 Church Street, Ann Arbor, MI, 48109-1065, USA.
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11
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Deshpande M, Papp S, Schaffer L, Pouyani T. Hydrocortisone and triiodothyronine regulate hyaluronate synthesis in a tissue-engineered human dermal equivalent through independent pathways. J Biosci Bioeng 2015; 119:226-36. [DOI: 10.1016/j.jbiosc.2014.08.001] [Citation(s) in RCA: 5] [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] [Received: 04/17/2014] [Revised: 07/24/2014] [Accepted: 08/04/2014] [Indexed: 10/24/2022]
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12
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Deshpande M, Papp S, Schaffer L, Pouyani T. Hydrocortisone effect on hyaluronate synthesis in a self-assembled human dermal equivalent. J Tissue Eng Regen Med 2013; 10:E316-E326. [PMID: 23955878 DOI: 10.1002/term.1809] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 06/26/2013] [Accepted: 07/19/2013] [Indexed: 11/08/2022]
Abstract
Human dermal matrix is a 'self-assembled' dermal equivalent containing large amounts of the glycosaminoglycan hyaluronic acid (hyaluronate, hyaluronan, HA). We sought to investigate the actions of the hormone hydrocortisone on hyaluronate synthesis in the human dermal matrix. To this end, human dermal fibroblasts were cultured under serum-free conditions, and in the absence of a three-dimensional matrix, in the presence of varying amounts of hydrocortisone. The resultant human dermal matrices were characterized. We report that low concentrations of hydrocortisone enhance hyaluronate synthesis in the human dermal equivalent and higher concentrations cause inhibition of hyaluronate synthesis. Other glycosaminoglycan (chondroitin sulphate) synthesis is not affected by changing hydrocortisone concentrations up to 500× (200 µg/ml) of the base value. In order to gain preliminary insight into the molecular mechanism of hyaluronate inhibition, a differential gene array analysis was conducted of human dermal matrix grown in the presence of 200 µg/ml hydrocortisone and in a physiological concentration (0.4 µg/ml, normal conditions). The results of these experiments demonstrate the differential expression of 43 genes in the 500× (200 µg/ml) hydrocortisone construct as compared to the construct grown under normal conditions (0.4 µg/ml hydrocortisone). These preliminary experiments suggest that hydrocortisone at higher concentrations may exert its inhibitory effect on hyaluronate synthesis early in the glycolytic pathway, leading to HA biosynthesis by downregulation of phosphoglucomutase and glucose phosphate isomerase, possibly leading to depletion of the cellular pool of UDP-sugar precursors necessary for HA synthesis. Copyright © 2013 John Wiley & Sons, Ltd.
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Affiliation(s)
- Madhura Deshpande
- Department of Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA
| | - Suzanne Papp
- DNA Array Core Facility, Scripps Research Institute, La Jolla, CA, USA
| | - Lana Schaffer
- DNA Array Core Facility, Scripps Research Institute, La Jolla, CA, USA
| | - Tara Pouyani
- Department of Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA.
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13
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Aggelis V, Craven RA, Peng J, Harnden P, Schaffer L, Hernandez GE, Head SR, Maher ER, Tonge R, Selby PJ, Banks RE. VHL-dependent regulation of a β-dystroglycan glycoform and glycogene expression in renal cancer. Int J Oncol 2013; 43:1368-76. [PMID: 23970118 PMCID: PMC3823392 DOI: 10.3892/ijo.2013.2066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [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: 06/26/2013] [Accepted: 07/30/2013] [Indexed: 12/27/2022] Open
Abstract
Identification of novel biomarkers and targets in renal cell carcinoma (RCC) remains a priority and one cellular compartment that is a rich potential source of such molecules is the plasma membrane. A shotgun proteomic analysis of cell surface proteins enriched by cell surface biotinylation and avidin affinity chromatography was explored using the UMRC2- renal cancer cell line, which lacks von Hippel-Lindau (VHL) tumour suppressor gene function, to determine whether proteins of interest could be detected. Of the 814 proteins identified ~22% were plasma membrane or membrane-associated, including several with known associations with cancer. This included β-dystroglycan, the transmembrane subunit of the DAG1 gene product. VHL-dependent changes in the form of β-dystroglycan were detected in UMRC2-/+VHL transfectants. Deglycosylation experiments showed that this was due to differential sialylation. Analysis of normal kidney cortex and conventional RCC tissues showed that a similar change also occurred in vivo. Investigation of the expression of genes involved in glycosylation in UMRC2-/+VHL cells using a focussed microarray highlighted a number of enzymes involved in sialylation; upregulation of bifunctional UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) was validated in UMRC2- cells compared with their +VHL counterparts and also found in conventional RCC tissue. These results implicate VHL in the regulation of glycosylation and raise interesting questions regarding the extent and importance of such changes in RCC.
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Affiliation(s)
- Vassilis Aggelis
- Cancer Research UK Centre, Leeds Institute of Cancer and Pathology, St. James's University Hospital, Leeds LS9 7TF, UK
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14
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Pouyani T, Sadaka BH, Papp S, Schaffer L. Triiodothyronine (T3) inhibits hyaluronate synthesis in a human dermal equivalent by downregulation of HAS2. In Vitro Cell Dev Biol Anim 2013; 49:178-88. [PMID: 23397370 DOI: 10.1007/s11626-013-9583-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 01/20/2013] [Indexed: 11/29/2022]
Abstract
Triiodothyronine (T3) is a thyroid hormone that can have varying effects on skin. In order to assess the effects of T3 on the human dermis, we prepared dermal equivalents using neonatal dermal cells via the process of self-assembly in the presence of differing concentrations of T3. These dermal equivalents were prepared in the absence of serum and a three dimensional matrix allowing for the direct assessment of different concentrations of T3 on dermal extracellular matrix formation. Three different concentrations of T3 were chosen, 20 pM, which is part of the base medium, 0.2 nM T3 and 2 nM T3. We find that self-assembled dermal equivalents formed under these conditions show a progressive "thinning" with increasing T3 concentrations. While we observed no change in total collagen content, inhibition of hyaluronate (HA) synthesis was observed in the 0.2- and 2-nM T3 constructs as compared to the 20-pM construct. Other glycosaminoglycan synthesis was not affected by increasing T3 concentrations. In order to identify the gene(s) responsible for inhibition of HA synthesis in the 2-nM T3 dermal equivalent, we conducted a differential gene array analysis. The results of these experiments demonstrate the differential expression of 40 genes, of these, 34 were upregulated and 6 genes were downregulated. The results from these experiments suggest that downregulation of HAS2 may be responsible for inhibition of hyaluronate synthesis in the self-assembled 2-nM T3 human dermal matrix.
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Affiliation(s)
- Tara Pouyani
- Department of Pharmaceutical Sciences, Northeastern University, Bouvé College of Health Sciences, Boston, MA, 02115, USA.
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15
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Verma-Gaur J, Torkamani A, Schaffer L, Head SR, Schork NJ, Feeney AJ. Noncoding transcription within the Igh distal V(H) region at PAIR elements affects the 3D structure of the Igh locus in pro-B cells. Proc Natl Acad Sci U S A 2012; 109:17004-9. [PMID: 23027941 PMCID: PMC3479473 DOI: 10.1073/pnas.1208398109] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [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] [Indexed: 12/16/2022] Open
Abstract
Noncoding sense and antisense germ-line transcription within the Ig heavy chain locus precedes V(D)J recombination and has been proposed to be associated with Igh locus accessibility, although its precise role remains elusive. However, no global analysis of germ-line transcription throughout the Igh locus has been done. Therefore, we performed directional RNA-seq, demonstrating the locations and extent of both sense and antisense transcription throughout the Igh locus. Surprisingly, the majority of antisense transcripts are localized around two Pax5-activated intergenic repeat (PAIR) elements in the distal IghV region. Importantly, long-distance loops measured by chromosome conformation capture (3C) are observed between these two active PAIR promoters and Eμ, the start site of Iμ germ-line transcription, in a lineage- and stage-specific manner, even though this antisense transcription is Eμ-independent. YY1(-/-) pro-B cells are greatly impaired in distal V(H) gene rearrangement and Igh locus compaction, and we demonstrate that YY1 deficiency greatly reduces antisense transcription and PAIR-Eμ interactions. ChIP-seq shows high level YY1 binding only at Eμ, but low levels near some antisense promoters. PAIR-Eμ interactions are not disrupted by DRB, which blocks transcription elongation without disrupting transcription factories once they are established, but the looping is reduced after heat-shock treatment, which disrupts transcription factories. We propose that transcription-mediated interactions, most likely at transcription factories, initially compact the Igh locus, bringing distal V(H) genes close to the DJ(H) rearrangement which is adjacent to Eμ. Therefore, we hypothesize that one key role of noncoding germ-line transcription is to facilitate locus compaction, allowing distal V(H) genes to undergo efficient rearrangement.
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Affiliation(s)
- Jiyoti Verma-Gaur
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
| | - Ali Torkamani
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, and The Scripps Translational Science Institute, La Jolla, CA 92037; and
| | - Lana Schaffer
- Next Generation Sequencing Core Facility, The Scripps Research Institute, La Jolla, CA 92037
| | - Steven R. Head
- Next Generation Sequencing Core Facility, The Scripps Research Institute, La Jolla, CA 92037
| | - Nicholas J. Schork
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, and The Scripps Translational Science Institute, La Jolla, CA 92037; and
| | - Ann J. Feeney
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
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16
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Gouveia R, Schaffer L, Papp S, Grammel N, Kandzia S, Head SR, Kleene R, Schachner M, Conradt HS, Costa J. Expression of glycogenes in differentiating human NT2N neurons. Downregulation of fucosyltransferase 9 leads to decreased Lewis(x) levels and impaired neurite outgrowth. Biochim Biophys Acta Gen Subj 2012; 1820:2007-19. [PMID: 23000574 DOI: 10.1016/j.bbagen.2012.09.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 09/07/2012] [Accepted: 09/10/2012] [Indexed: 12/12/2022]
Abstract
BACKGROUND Several glycan structures are functionally relevant in biological events associated with differentiation and regeneration which occur in the central nervous system. Here we have analysed the glycogene expression and glycosylation patterns during human NT2N neuron differentiation. We have further studied the impact of downregulating fucosyltransferase 9 (FUT9) on neurite outgrowth. METHODS The expression of glycogenes in human NT2N neurons differentiating from teratocarcinoma NTERA-2/cl.D1 cells has been analysed using the GlycoV4 GeneChip expression microarray. Changes in glycosylation have been monitored by immunoblot, immunofluorescence microscopy, HPLC and MALDI-TOF MS. Peptide mass fingerprinting and immunoprecipitation have been used for protein identification. FUT9 was downregulated using silencing RNA. RESULTS AND CONCLUSIONS One hundred twelve mRNA transcripts showed statistically significant up-regulation, including the genes coding for proteins involved in the synthesis of the Lewis(x) motif (FUT9), polysialic acid (ST8SIA2 and ST8SIA4) and HNK-1 (B3GAT2). Accordingly, increased levels of the corresponding carbohydrate epitopes have been observed. The Lewis(x) structure was found in a carrier glycoprotein that was identified as the CRA-a isoform of human neural cell adhesion molecule 1. Downregulation of FUT9 caused significant decreases in the levels of Lewis(x), as well as GAP-43, a marker of neurite outgrowth. Concomitantly, a reduction in neurite formation and outgrowth has been observed that was reversed by FUT9 overexpression. GENERAL SIGNIFICANCE These results provided information about the regulation of glycogenes during neuron differentiation and they showed that the Lewis(x) motif plays a functional role in neurite outgrowth from human neurons.
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Affiliation(s)
- Ricardo Gouveia
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, Oeiras, Portugal
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17
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Van Nieuwerburgh F, Soetaert S, Podshivalova K, Ay-Lin Wang E, Schaffer L, Deforce D, Salomon DR, Head SR, Ordoukhanian P. Quantitative bias in Illumina TruSeq and a novel post amplification barcoding strategy for multiplexed DNA and small RNA deep sequencing. PLoS One 2011; 6:e26969. [PMID: 22046424 PMCID: PMC3203936 DOI: 10.1371/journal.pone.0026969] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [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: 08/19/2011] [Accepted: 10/06/2011] [Indexed: 01/29/2023] Open
Abstract
Here we demonstrate a method for unbiased multiplexed deep sequencing of RNA and DNA libraries using a novel, efficient and adaptable barcoding strategy called Post Amplification Ligation-Mediated (PALM). PALM barcoding is performed as the very last step of library preparation, eliminating a potential barcode-induced bias and allowing the flexibility to synthesize as many barcodes as needed. We sequenced PALM barcoded micro RNA (miRNA) and DNA reference samples and evaluated the quantitative barcode-induced bias in comparison to the same reference samples prepared using the Illumina TruSeq barcoding strategy. The Illumina TruSeq small RNA strategy introduces the barcode during the PCR step using differentially barcoded primers, while the TruSeq DNA strategy introduces the barcode before the PCR step by ligation of differentially barcoded adaptors. Results show virtually no bias between the differentially barcoded miRNA and DNA samples, both for the PALM and the TruSeq sample preparation methods. We also multiplexed miRNA reference samples using a pre-PCR barcode ligation. This barcoding strategy results in significant bias.
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18
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Julien S, Ivetic A, Grigoriadis A, QiZe D, Burford B, Sproviero D, Picco G, Gillett C, Papp SL, Schaffer L, Tutt A, Taylor-Papadimitriou J, Pinder SE, Burchell JM. Selectin ligand sialyl-Lewis x antigen drives metastasis of hormone-dependent breast cancers. Cancer Res 2011; 71:7683-93. [PMID: 22025563 DOI: 10.1158/0008-5472.can-11-1139] [Citation(s) in RCA: 139] [Impact Index Per Article: 10.7] [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
The glycome acts as an essential interface between cells and the surrounding microenvironment. However, changes in glycosylation occur in nearly all breast cancers, which can alter this interaction. Here, we report that profiles of glycosylation vary between ER-positive and ER-negative breast cancers. We found that genes involved in the synthesis of sialyl-Lewis x (sLe(x); FUT3, FUT4, and ST3GAL6) are significantly increased in estrogen receptor alpha-negative (ER-negative) tumors compared with ER-positive ones. SLe(x) expression had no influence on the survival of patients whether they had ER-negative or ER-positive tumors. However, high expression of sLe(x) in ER-positive tumors was correlated with metastasis to the bone where sLe(x) receptor E-selectin is constitutively expressed. The ER-positive ZR-75-1 and the ER-negative BT20 cell lines both express sLe(x) but only ZR-75-1 cells could adhere to activated endothelial cells under dynamic flow conditions in a sLe(x) and E-selectin-dependent manner. Moreover, L/P-selectins bound strongly to ER-negative MDA-MB-231 and BT-20 cell lines in a heparan sulfate (HS)-dependent manner that was independent of sLe(x) expression. Expression of glycosylation genes involved in heparan biosynthesis (EXT1 and HS3ST1) was increased in ER-negative tumors. Taken together, our results suggest that the context of sLe(x) expression is important in determining its functional significance and that selectins may promote metastasis in breast cancer through protein-associated sLe(x) and HS glycosaminoglycans.
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Affiliation(s)
- Sylvain Julien
- Breast Cancer Biology, King's College London, Guy's Hospital, London, United Kingdom
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19
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Tang B, Di Lena P, Schaffer L, Head SR, Baldi P, Thomas EA. Genome-wide identification of Bcl11b gene targets reveals role in brain-derived neurotrophic factor signaling. PLoS One 2011; 6:e23691. [PMID: 21912641 PMCID: PMC3164671 DOI: 10.1371/journal.pone.0023691] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 07/22/2011] [Indexed: 01/01/2023] Open
Abstract
B-cell leukemia/lymphoma 11B (Bcl11b) is a transcription factor showing predominant expression in the striatum. To date, there are no known gene targets of Bcl11b in the nervous system. Here, we define targets for Bcl11b in striatal cells by performing chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) in combination with genome-wide expression profiling. Transcriptome-wide analysis revealed that 694 genes were significantly altered in striatal cells over-expressing Bcl11b, including genes showing striatal-enriched expression similar to Bcl11b. ChIP-seq analysis demonstrated that Bcl11b bound a mixture of coding and non-coding sequences that were within 10 kb of the transcription start site of an annotated gene. Integrating all ChIP-seq hits with the microarray expression data, 248 direct targets of Bcl11b were identified. Functional analysis on the integrated gene target list identified several zinc-finger encoding genes as Bcl11b targets, and further revealed a significant association of Bcl11b to brain-derived neurotrophic factor/neurotrophin signaling. Analysis of ChIP-seq binding regions revealed significant consensus DNA binding motifs for Bcl11b. These data implicate Bcl11b as a novel regulator of the BDNF signaling pathway, which is disrupted in many neurological disorders. Specific targeting of the Bcl11b-DNA interaction could represent a novel therapeutic approach to lowering BDNF signaling specifically in striatal cells.
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Affiliation(s)
- Bin Tang
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Pietro Di Lena
- Department of Computer Science and Institute for Genomics and Bioinformatics, University of California, Irvine, Irvine, California, United States of America
| | - Lana Schaffer
- Department of Shared Research Services, The Scripps Research Institute, La Jolla, California, United States of America
| | - Steven R. Head
- Department of Shared Research Services, The Scripps Research Institute, La Jolla, California, United States of America
| | - Pierre Baldi
- Department of Computer Science and Institute for Genomics and Bioinformatics, University of California, Irvine, Irvine, California, United States of America
| | - Elizabeth A. Thomas
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California, United States of America
- * E-mail:
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20
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Mitra N, Banda K, Altheide TK, Schaffer L, Johnson-Pais TL, Beuten J, Leach RJ, Angata T, Varki N, Varki A. SIGLEC12, a human-specific segregating (pseudo)gene, encodes a signaling molecule expressed in prostate carcinomas. J Biol Chem 2011; 286:23003-11. [PMID: 21555517 PMCID: PMC3123068 DOI: 10.1074/jbc.m111.244152] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [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: 03/30/2011] [Revised: 05/05/2011] [Indexed: 12/15/2022] Open
Abstract
The primate SIGLEC12 gene encodes one of the CD33-related Siglec family of signaling molecules in immune cells. We had previously reported that this gene harbors a human-specific missense mutation of the codon for an Arg residue required for sialic acid recognition. Here we show that this R122C mutation of the Siglec-XII protein is fixed in the human population, i.e. it occurred prior to the origin of modern humans. Additional mutations have since completely inactivated the SIGLEC12 gene in some but not all humans. The most common inactivating mutation with a global allele frequency of 58% is a single nucleotide frameshift that markedly shortens the open reading frame. Unlike other CD33-related Siglecs that are primarily found on immune cells, we found that Siglec-XII protein is expressed not only on some macrophages but also on various epithelial cell surfaces in humans and chimpanzees. We also found expression on certain human prostate epithelial carcinomas and carcinoma cell lines. This expression correlates with the presence of the nonframeshifted, intact SIGLEC12 allele. Although SIGLEC12 allele status did not predict prostate carcinoma incidence, restoration of expression in a prostate carcinoma cell line homozygous for the frameshift mutation induced altered regulation of several genes associated with carcinoma progression. These stably transfected Siglec-XII-expressing prostate cancer cells also showed enhanced growth in nude mice. Finally, monoclonal antibodies against the protein were internalized by Siglec-XII-expressing prostate carcinoma cells, allowing targeting of a toxin to such cells. Polymorphic expression of Siglec-XII in humans thus has implications for prostate cancer biology and therapeutics.
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Affiliation(s)
- Nivedita Mitra
- From the Glycobiology Research and Training Center, Departments of Medicine, Pathology and Cellular & Molecular Medicine, University of California at San Diego, La Jolla, California 92093
| | - Kalyan Banda
- From the Glycobiology Research and Training Center, Departments of Medicine, Pathology and Cellular & Molecular Medicine, University of California at San Diego, La Jolla, California 92093
| | - Tasha K. Altheide
- From the Glycobiology Research and Training Center, Departments of Medicine, Pathology and Cellular & Molecular Medicine, University of California at San Diego, La Jolla, California 92093
| | - Lana Schaffer
- the Scripps Research Institute, La Jolla, California 92037, and
| | - Teresa L. Johnson-Pais
- the Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Joke Beuten
- the Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Robin J. Leach
- the Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Takashi Angata
- From the Glycobiology Research and Training Center, Departments of Medicine, Pathology and Cellular & Molecular Medicine, University of California at San Diego, La Jolla, California 92093
| | - Nissi Varki
- From the Glycobiology Research and Training Center, Departments of Medicine, Pathology and Cellular & Molecular Medicine, University of California at San Diego, La Jolla, California 92093
| | - Ajit Varki
- From the Glycobiology Research and Training Center, Departments of Medicine, Pathology and Cellular & Molecular Medicine, University of California at San Diego, La Jolla, California 92093
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Barthel SR, Antonopoulos A, Cedeno-Laurent F, Schaffer L, Hernandez G, Patil SA, North SJ, Dell A, Matta KL, Neelamegham S, Haslam SM, Dimitroff CJ. Peracetylated 4-fluoro-glucosamine reduces the content and repertoire of N- and O-glycans without direct incorporation. J Biol Chem 2011; 286:21717-31. [PMID: 21493714 PMCID: PMC3122228 DOI: 10.1074/jbc.m110.194597] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 04/12/2011] [Indexed: 12/21/2022] Open
Abstract
Prior studies have shown that treatment with the peracetylated 4-fluorinated analog of glucosamine (4-F-GlcNAc) elicits anti-skin inflammatory activity by ablating N-acetyllactosamine (LacNAc), sialyl Lewis X (sLe(X)), and related lectin ligands on effector leukocytes. Based on anti-sLe(X) antibody and lectin probing experiments on 4-F-GlcNAc-treated leukocytes, it was hypothesized that 4-F-GlcNAc inhibited sLe(X) formation by incorporating into LacNAc and blocking the addition of galactose or fucose at the carbon 4-position of 4-F-GlcNAc. To test this hypothesis, we determined whether 4-F-GlcNAc is directly incorporated into N- and O-glycans released from 4-F-GlcNAc-treated human sLe(X) (+) T cells and leukemic KG1a cells. At concentrations that abrogated galectin-1 (Gal-1) ligand and E-selectin ligand expression and related LacNAc and sLe(X) structures, MALDI-TOF and MALDI-TOF/TOF mass spectrometry analyses showed that 4-F-GlcNAc 1) reduced content and structural diversity of tri- and tetra-antennary N-glycans and of O-glycans, 2) increased biantennary N-glycans, and 3) reduced LacNAc and sLe(X) on N-glycans and on core 2 O-glycans. Moreover, MALDI-TOF MS did not reveal any m/z ratios relating to the presence of fluorine atoms, indicating that 4-F-GlcNAc did not incorporate into glycans. Further analysis showed that 4-F-GlcNAc treatment had minimal effect on expression of 1200 glycome-related genes and did not alter the activity of LacNAc-synthesizing enzymes. However, 4-F-GlcNAc dramatically reduced intracellular levels of uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc), a key precursor of LacNAc synthesis. These data show that Gal-1 and E-selectin ligand reduction by 4-F-GlcNAc is not caused by direct 4-F-GlcNAc glycan incorporation and consequent chain termination but rather by interference with UDP-GlcNAc synthesis.
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Affiliation(s)
- Steven R. Barthel
- From the Harvard Skin Disease Research Center, Department of Dermatology, and
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Aristotelis Antonopoulos
- the Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Filiberto Cedeno-Laurent
- From the Harvard Skin Disease Research Center, Department of Dermatology, and
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Lana Schaffer
- Scripps Research Institute, La Jolla, California 92037
| | | | - Shilpa A. Patil
- the Department of Chemical and Biological Engineering, State University of New York, Buffalo, New York 14260, and
| | - Simon J. North
- the Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Anne Dell
- the Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Khushi L. Matta
- the Department of Cancer Biology, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Sriram Neelamegham
- the Department of Chemical and Biological Engineering, State University of New York, Buffalo, New York 14260, and
| | - Stuart M. Haslam
- the Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Charles J. Dimitroff
- From the Harvard Skin Disease Research Center, Department of Dermatology, and
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
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Chang LM, Maheshwari P, Werth S, Schaffer L, Head SR, Kovarik C, Werth VP. Identification and molecular analysis of glycosaminoglycans in cutaneous lupus erythematosus and dermatomyositis. J Histochem Cytochem 2011; 59:336-45. [PMID: 21378287 DOI: 10.1369/0022155410398000] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Glycosaminoglycans (GAGs), also known histologically as dermal mucin, accumulate in several inflammatory skin conditions. Because different GAG species have distinct immunologic effects, the authors examined two GAGs, hyaluronan (HA) and chondroitin sulfate (CS), using specific stains in cutaneous lupus erythematosus (CLE) and dermatomyositis (DM). In the dermis of one CLE subtype, tumid LE (TLE), they found only increased HA, but both HA and CS were significantly elevated in another CLE subtype, discoid LE (DLE). DM lesional dermis accumulated mainly CS but not HA. The authors then used glycomic gene expression microarrays to assess the expression of HA- and CS-related genes in CLE skin. Real-time quantitative PCR confirmed significantly increased expression of HAS2, CHSY1, and C4ST1 in the combined groups of CLE lesions (n = 8) compared to healthy controls (n = 4). Thus, the increase in HA in CLE presumably results from upregulation of HAS2, whereas CHSY1 and C4ST1 appear to contribute to increased CS. Based on their known immunomodulatory effects in other systems, HA and CS may thus participate in the pathophysiology of these inflammatory skin conditions.
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Affiliation(s)
- Laura M Chang
- Philadelphia VA Medical Center, Philadelphia, Pennsylvania, USA
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Chen K, Liu ML, Schaffer L, Li M, Boden G, Wu X, Williams KJ. Type 2 diabetes in mice induces hepatic overexpression of sulfatase 2, a novel factor that suppresses uptake of remnant lipoproteins. Hepatology 2010; 52:1957-67. [PMID: 21049473 PMCID: PMC2991429 DOI: 10.1002/hep.23916] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [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: 12/23/2009] [Accepted: 08/03/2010] [Indexed: 12/22/2022]
Abstract
UNLABELLED Type 2 diabetes mellitus (T2DM) impairs hepatic clearance of atherogenic postprandial remnant lipoproteins. Our work and that of others have identified syndecan-1 heparan sulfate proteoglycans (HSPGs) as remnant lipoprotein receptors. Nevertheless, defects in the T2DM liver have not been molecularly characterized, and neither has the correction that occurs upon caloric restriction. We used microarrays to compare expression of proteoglycan-related genes in livers from control db/m mice; obese, T2DM db/db littermates fed ad libitum (AL); and db/db mice pair-fed to match the intake of db/m mice. Surprisingly, the arrays identified only one gene whose dysregulation by T2DM would disrupt HSPG structure: the heparan sulfate glucosamine-6-O-endosulfatase-2 (Sulf2). SULF2 degrades HSPGs by removing 6-O sulfate groups, but had no previously known role in diabetes or lipoprotein biology. Follow-up quantitative polymerase chain reaction assays revealed a striking 11-fold induction of Sulf2 messenger RNA in the livers of AL T2DM mice compared with controls. Immunoblots demonstrated induction of SULF2 in AL livers, with restoration toward normal in livers from pair-fed db/db mice. Knockdown of SULF2 in cultured hepatocytes doubled HSPG-mediated catabolism of model remnant lipoproteins. Notably, co-immunoprecipitations revealed a persistent physical association of SULF2 with syndecan-1. To identify mechanisms of SULF2 dysregulation in T2DM, we found that advanced glycosylation end products provoked a 10-fold induction in SULF2 expression by cultured hepatocytes and an approximately 50% impairment in their catabolism of remnants and very low-density lipoprotein, an effect that was entirely reversed by SULF2 knockdown. Adiponectin and insulin each suppressed SULF2 protein in cultured liver cells and in murine livers in vivo, consistent with a role in energy flux. Likewise, both hormones enhanced remnant lipoprotein catabolism in vitro. CONCLUSION SULF2 is an unexpected suppressor of atherogenic lipoprotein clearance by hepatocytes and an attractive target for inhibition.
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Affiliation(s)
- Keyang Chen
- Temple University School of Medicine, Philadelphia, PA USA
| | - Ming-Lin Liu
- Temple University School of Medicine, Philadelphia, PA USA
| | - Lana Schaffer
- Consortium for Functional Glycomics, Scripps Research Institute, La Jolla, CA USA
| | - Mingzhen Li
- Temple University School of Medicine, Philadelphia, PA USA
| | - Guenther Boden
- Temple University School of Medicine, Philadelphia, PA USA
| | - Xiangdong Wu
- Temple University School of Medicine, Philadelphia, PA USA
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Guan F, Schaffer L, Handa K, Hakomori SI. Functional role of gangliotetraosylceramide in epithelial‐to‐mesenchymal transition process induced by hypoxia and by TGF‐β. FASEB J 2010. [DOI: 10.1096/fj.10.162107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Feng Guan
- Division of Biomembrane ResearchPacific Northwest Research Institute Seattle Washington USA
- Departments of Pathobiology and Global HealthUniversity of Washington Seattle Washington USA
| | - Lana Schaffer
- Division of Biomembrane ResearchPacific Northwest Research Institute Seattle Washington USA
- DNA Array Core FacilityThe Scripps Research Institute La Jolla California USA
| | - Kazuko Handa
- Division of Biomembrane ResearchPacific Northwest Research Institute Seattle Washington USA
- Departments of Pathobiology and Global HealthUniversity of Washington Seattle Washington USA
| | - Sen-itiroh Hakomori
- Division of Biomembrane ResearchPacific Northwest Research Institute Seattle Washington USA
- Departments of Pathobiology and Global HealthUniversity of Washington Seattle Washington USA
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Guan F, Schaffer L, Handa K, Hakomori SI. Functional role of gangliotetraosylceramide in epithelial-to-mesenchymal transition process induced by hypoxia and by TGF-{beta}. FASEB J 2010; 24:4889-903. [PMID: 20720159 DOI: 10.1096/fj.10-162107] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The epithelial-to-mesenchymal transition (EMT) is a basic cellular process that plays a key role in normal embryonic development and in cancer progression/metastasis. Our previous study indicated that EMT processes of mouse and human epithelial cells induced by TGF-β display clear reduction of gangliotetraosylceramide (Gg4) and ganglioside GM2, suggesting a close association of glycosphingolipids (GSLs) with EMT. In the present study, using normal murine mammary gland (NMuMG) cells, we found that levels of Gg4 and of mRNA for the UDP-Gal:β1-3galactosyltransferase-4 (β3GalT4) gene, responsible for reduction of Gg4, were reduced in EMT induced by hypoxia (∼1% O(2)) or CoCl(2) (hypoxia mimic), similarly to that for TGF-β-induced EMT. An increase in the Gg4 level by its exogenous addition or by transfection of the β3GalT4 gene inhibited the hypoxia-induced or TGF-β-induced EMT process, including changes in epithelial cell morphology, enhanced motility, and associated changes in epithelial vs. mesenchymal molecules. We also found that Gg4 is closely associated with E-cadherin and β-catenin. These results suggest that the β3GalT4 gene, responsible for Gg4 expression, is down-regulated in EMT; and Gg4 has a regulatory function in the EMT process in NMuMG cells, possibly through interaction with epithelial molecules important to maintain epithelial cell membrane organization.
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Affiliation(s)
- Feng Guan
- Division of Biomembrane Research, Pacific Northwest Research Institute, Seattle, Washington 98122, USA
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Rozenzhak S, Mejía-Ramírez E, Williams JS, Schaffer L, Hammond JA, Head SR, Russell P. Rad3 decorates critical chromosomal domains with gammaH2A to protect genome integrity during S-Phase in fission yeast. PLoS Genet 2010; 6:e1001032. [PMID: 20661445 PMCID: PMC2908685 DOI: 10.1371/journal.pgen.1001032] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Accepted: 06/17/2010] [Indexed: 01/24/2023] Open
Abstract
Schizosaccharomyces pombe Rad3 checkpoint kinase and its human ortholog ATR are essential for maintaining genome integrity in cells treated with genotoxins that damage DNA or arrest replication forks. Rad3 and ATR also function during unperturbed growth, although the events triggering their activation and their critical functions are largely unknown. Here, we use ChIP-on-chip analysis to map genomic loci decorated by phosphorylated histone H2A (γH2A), a Rad3 substrate that establishes a chromatin-based recruitment platform for Crb2 and Brc1 DNA repair/checkpoint proteins. Unexpectedly, γH2A marks a diverse array of genomic features during S-phase, including natural replication fork barriers and a fork breakage site, retrotransposons, heterochromatin in the centromeres and telomeres, and ribosomal RNA (rDNA) repeats. γH2A formation at the centromeres and telomeres is associated with heterochromatin establishment by Clr4 histone methyltransferase. We show that γH2A domains recruit Brc1, a factor involved in repair of damaged replication forks. Brc1 C-terminal BRCT domain binding to γH2A is crucial in the absence of Rqh1Sgs1, a RecQ DNA helicase required for rDNA maintenance whose human homologs are mutated in patients with Werner, Bloom, and Rothmund–Thomson syndromes that are characterized by cancer-predisposition or accelerated aging. We conclude that Rad3 phosphorylates histone H2A to mobilize Brc1 to critical genomic domains during S-phase, and this pathway functions in parallel with Rqh1 DNA helicase in maintaining genome integrity. Eukaryotic genomes, which range in size from ∼107 to ∼1011 base pairs, are replicated with nearly absolute fidelity every cell cycle. This amazing feat happens despite the frequent stalling or collapse of replication forks. The checkpoint kinase ATR is activated by replication fork stalling and phosphorylates histone H2A in nucleosomes surrounding damaged DNA. As the genomic regions triggering ATR activation are largely unknown, we used a whole-genome microarray to map chromosomal domains enriched with phospho-H2A during DNA replication in fission yeast. This analysis identified specific sites, including natural replication fork barriers in ribosomal DNA repeats, retrotransposon elements, and most surprisingly, all heterochromatin regions. Phospho-H2A binds the genome maintenance protein Brc1, and our genetic studies reveal that this molecular pathway becomes crucial in the absence of Rqh1, a conserved DNA helicase that is linked to cancer predisposition. As the fission yeast and human genomes share many similarities, our study reveals genomic landmarks that could similarly trigger ATR activation in human cells and shows that phospho-H2A and Brc1 are a critical part of the network that maintains genome integrity during DNA replication.
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Affiliation(s)
- Sophie Rozenzhak
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Eva Mejía-Ramírez
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Jessica S. Williams
- Laboratory of Structural Biology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, United States of America
| | - Lana Schaffer
- DNA Array Core Facility, The Scripps Research Institute, La Jolla, California, United States of America
| | - Jennifer A. Hammond
- DNA Array Core Facility, The Scripps Research Institute, La Jolla, California, United States of America
| | - Steven R. Head
- DNA Array Core Facility, The Scripps Research Institute, La Jolla, California, United States of America
| | - Paul Russell
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California, United States of America
- Department of Cell Biology, The Scripps Research Institute, La Jolla, California, United States of America
- * E-mail:
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Jensen K, Schaffer L, Olstad OK, Bechensteen AG, Hellebostad M, Tjønnfjord GE, Kierulf P, Gautvik KM, Osnes LTN. Striking decrease in the total precursor B-cell compartment during early childhood as evidenced by flow cytometry and gene expression changes. Pediatr Hematol Oncol 2010; 27:31-45. [PMID: 20121553 DOI: 10.3109/08880010903420687] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The number of circulating B-cells in peripheral blood plateaus between 2 and 24 months of age, and thereafter declines gradually. How this reflects the kinetics of the precursor B-cell pool in the bone marrow is of clinical interest, but has not been studied thoroughly in humans. The authors analyzed bone marrow (n = 37) from healthy children and adults (flow cytometry) searching for age-related changes in the total precursor B-cell compartment. In an age-matched cohort (n = 25) they examined age-related global gene expression changes (Affymetrix) in unsorted bone marrow with special reference to the recombination activating gene 1, RAG1. Subsequently, they searched the entire gene set for transcripts correlating to the RAG1 profile to discover other known and possibly new precursor B-cell related transcripts. Both methods disclosed a marked, transient increase of total precursor B-cells at 6-20 months, followed by a rapid decrease confined to the first 2 years. The decline thereafter was considerably slower, but continued until adulthood. The relative composition of total precursor B-cells, however, did not change significantly with age. The authors identified 54 genes that were highly correlated to the RAG1 profile (r >or= .9, p < 1 x 10(-8)). Of these 54 genes, 15 were characteristically B-lineage associated like CD19, CD79, VPREB, EBF1, and PAX5; the remaining 39 previously not described as distinctively B-lineage related. The marked, transient increase in precursor B-cells and RAG1 transcriptional activity is not reflected by a similar peak in B-cells in peripheral blood, whereas the sustained plateau concurs in time.
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Affiliation(s)
- Kristin Jensen
- Department of Pediatrics, Faculty Division Ullevål, University of Oslo, Oslo, Norway.
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Chen K, Liu ML, Schaffer L, Li M, Williams KJ. Abstract: 540 TYPE 2 DIABETES STRONGLY INDUCES HEPATIC OVEREXPRESSION OF SULF2, A NOVEL FACTOR THAT SUPPRESSES UPTAKE OF REMNANT LIPOPROTEINS. ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)70280-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [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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Mantelli F, Schaffer L, Dana R, Head SR, Argüeso P. Glycogene expression in conjunctiva of patients with dry eye: downregulation of Notch signaling. Invest Ophthalmol Vis Sci 2008; 50:2666-72. [PMID: 19011014 DOI: 10.1167/iovs.08-2734] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Glycoconjugates regulate a variety of biological events in mucosal surfaces, such as differentiation of postmitotic epithelial cells and maintenance of the wet-surfaced phenotype. This study aimed to identify the repertoire of genes (glycogenes) involved in biosynthesis of glycoconjugates in conjunctiva of normal subjects and patients with dry eye. METHODS RNA from conjunctival impression cytology samples was amplified and hybridized to a custom-designed glycogene microarray. Intensity data were converted to expression values and analyzed by ANOVA. Microarray data for selected Notch glycogenes were confirmed by quantitative real-time PCR. Notch receptors and ligands were immunolocalized on conjunctival biopsies by confocal microscopy. RESULTS By microarray, 424 glycogenes were identified in normal conjunctival epithelium; galectins, glycosyltransferases, mucins, Notch signaling molecules, and proteoglycans were among the most highly expressed. In dry eye, 46 glycogenes were significantly downregulated, including five members of the Notch signaling pathway (Notch1, Notch 2, Notch 3, Jagged1, Delta1), four Wnt signaling molecules (Wnt4, -5A, Frizzled6, -7), and three heparan sulfate glycotransferases (HS2ST1, HS3ST6, EXTL2). Only interferon-induced transmembrane protein 1 was upregulated. By real-time PCR, expression ratios of Notch1, Notch 3, and Jagged1 in dry eye were 0.43, 0.56, and 0.50, respectively, compared to controls (P < 0.05). Notch1, Notch3, and Jagged1 were immunolocalized throughout the conjunctival epithelium, whereas Notch2 and Delta1 were distributed apically. CONCLUSIONS This study revealed the differential glycogene expression profiles in normal subjects and patients with dry eye. Downregulation of Notch signaling in dry eye may result in abnormal differentiation of the conjunctival epithelium and have implications in the pathogenesis of the disease.
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Affiliation(s)
- Flavio Mantelli
- Department of Ophthalmology, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts 02114, USA
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Pebernard S, Schaffer L, Campbell D, Head SR, Boddy MN. Localization of Smc5/6 to centromeres and telomeres requires heterochromatin and SUMO, respectively. EMBO J 2008; 27:3011-23. [PMID: 18923417 DOI: 10.1038/emboj.2008.220] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Accepted: 09/22/2008] [Indexed: 01/19/2023] Open
Abstract
The Smc5/6 holocomplex executes key functions in genome maintenance that include ensuring the faithful segregation of chromosomes at mitosis and facilitating critical DNA repair pathways. Smc5/6 is essential for viability and therefore, dissecting its chromosome segregation and DNA repair roles has been challenging. We have identified distinct epigenetic and post-translational modifications that delineate roles for fission yeast Smc5/6 in centromere function, versus replication fork-associated DNA repair. We monitored Smc5/6 subnuclear and genomic localization in response to different replicative stresses, using fluorescence microscopy and chromatin immunoprecipitation (ChIP)-on-chip methods. Following hydroxyurea treatment, and during an unperturbed S phase, Smc5/6 is transiently enriched at the heterochromatic outer repeats of centromeres in an H3-K9 methylation-dependent manner. In contrast, methyl methanesulphonate treatment induces the accumulation of Smc5/6 at subtelomeres, in an Nse2 SUMO ligase-dependent, but H3-K9 methylation-independent manner. Finally, we determine that Smc5/6 loads at all genomic tDNAs, a phenomenon that requires intact consensus TFIIIC-binding sites in the tDNAs.
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Affiliation(s)
- Stephanie Pebernard
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
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31
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Assarsson E, Greenbaum JA, Sundstrom M, Schaffer L, Pasquetto V, Oseroff C, Tscharke D, Sidney J, Grey H, Head S, Peters B, Sette A. Kinetic Analysis of a Complete Poxvirus Transcriptome Reveals a Novel Class of Genes. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.855.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Erika Assarsson
- Division of Vaccine DiscoveryLa Jolla Institute for Allergy and ImmunologyLa JollaCA
| | - Jason A. Greenbaum
- Division of Vaccine DiscoveryLa Jolla Institute for Allergy and ImmunologyLa JollaCA
| | | | - Lana Schaffer
- DNA array core facilityThe Scripps Research InstituteLa JollaCA
| | - Valerie Pasquetto
- Division of Vaccine DiscoveryLa Jolla Institute for Allergy and ImmunologyLa JollaCA
| | - Carla Oseroff
- Division of Vaccine DiscoveryLa Jolla Institute for Allergy and ImmunologyLa JollaCA
| | - David Tscharke
- School of Biochemistry and Molecular BiologyThe Australian National UniversityCanberraAustralia
| | - John Sidney
- Division of Vaccine DiscoveryLa Jolla Institute for Allergy and ImmunologyLa JollaCA
| | - Howard Grey
- Division of Vaccine DiscoveryLa Jolla Institute for Allergy and ImmunologyLa JollaCA
| | - Steven Head
- DNA array core facilityThe Scripps Research InstituteLa JollaCA
| | - Bjoern Peters
- Division of Vaccine DiscoveryLa Jolla Institute for Allergy and ImmunologyLa JollaCA
| | - Alessandro Sette
- Division of Vaccine DiscoveryLa Jolla Institute for Allergy and ImmunologyLa JollaCA
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Croker B, Crozat K, Berger M, Xia Y, Sovath S, Schaffer L, Eleftherianos I, Imler JL, Beutler B. ATP-sensitive potassium channels mediate survival during infection in mammals and insects. Nat Genet 2007; 39:1453-60. [DOI: 10.1038/ng.2007.25] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2007] [Accepted: 09/04/2007] [Indexed: 11/09/2022]
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Weinberg MS, Barichievy S, Schaffer L, Han J, Morris KV. An RNA targeted to the HIV-1 LTR promoter modulates indiscriminate off-target gene activation. Nucleic Acids Res 2007; 35:7303-12. [PMID: 17959645 PMCID: PMC2175361 DOI: 10.1093/nar/gkm847] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Transcriptional gene silencing (TGS) can be achieved by small RNAs targeted to upstream promoter regions. Previously we characterized siRNAs targeted to the HIV-1 long terminal repeat (LTR) promoter at site 247, and found that a 21-base antisense strand of siRNA-247 (LTR-247as) suppressed LTR-mediated expression. To characterize the specificity of LTR-247as, vectors expressing antisense RNAs targeted to a region spanning 50 bases up- and downstream of the 247 target site were generated. LTR-247as+7, a approximately 22 base antisense RNA that is shifted by only seven bases upstream of LTR-247as, showed a significant increase in LTR-driven reporter gene expression that was independent of cell type and active chromatin methyl-marks. Promoter-targeting siRNAs have been recently shown to induce gene activation. However, here we demonstrate gene activation via a sequence-specific off-target effect. Microarray analysis of LTR-247as+7-treated cultures resulted in the deregulation of approximately 185 genes. A gene of unknown function, C10orf76, was responsive to inhibition by LTR-247as+7 and the loss of C10orf76 resulted in the upregulation of several genes that were activated by LTR-247as+7. These data suggest caution when using short antisense RNAs or siRNAs designed to target promoter sequences, since promoter-targeted RNAs may have unintended inhibitory effects against factors with suppressive gene activity.
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Affiliation(s)
- Marc S Weinberg
- Antiviral Gene Therapy Research Unit, Department of Molecular Medicine and Haematology, University of the Witwatersrand Medical School, 7 York Rd Parktown 2193, South Africa
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Kobayashi M, Lee H, Schaffer L, Gilmartin TJ, Head SR, Takaishi S, Wang TC, Nakayama J, Fukuda M. A distinctive set of genes is upregulated during the inflammation-carcinoma sequence in mouse stomach infected by Helicobacter felis. J Histochem Cytochem 2006; 55:263-74. [PMID: 17101721 DOI: 10.1369/jhc.6a7097.2006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Helicobacter pylori infects over half the population worldwide and is a leading cause of chronic gastritis and gastric cancer. However, the mechanism by which this organism induces inflammation and carcinogenesis is not fully understood. In the present study we used insulin-gastrin (INS-GAS) transgenic mice that fully develop gastric adenocarcinoma after infection of H. pylori-related Helicobacter felis. Histological examination revealed that more than half of those mice developed invasive adenocarcinoma after 8 months of infection. These carcinomas were stained by NCC-ST-439 and HECA-452 that recognize 6-sulfated and non-sulfated sialyl Lewis X. Lymphocytic infiltration predominantly to submucosa was observed in most H. felis-infected mice, and this was associated with the formation of peripheral lymph node addressin (PNAd) on high endothelial venule (HEV)-like vessels detected by MECA-79. Time-course analysis of gene expression by using gene microarray revealed upregulation of several inflammation-associated genes including chemokines, adhesion molecules, surfactant protein D (SP-D), and CD74 in the infected stomach. Immunohistochemical analysis demonstrated that SP-D is expressed in hyperplasia and adenocarcinoma whereas CD74 is expressed in adenocarcinoma in situ and invasive carcinoma. These results as a whole indicate that H. felis induces HEV-like vessels and inflammation-associated chemokines and chemokine receptors, followed by adenocarcinoma formation.
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Affiliation(s)
- Motohiro Kobayashi
- Glycobiology Program, Cancer Research Center, Burnham Institute for Medical Research, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
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Verkhivker GM, Bouzida D, Gehlhaar DK, Rejto PA, Schaffer L, Arthurs S, Colson AB, Freer ST, Larson V, Luty BA, Marrone T, Rose PW. Hierarchy of simulation models in predicting structure and energetics of the Src SH2 domain binding to tyrosyl phosphopeptides. J Med Chem 2002; 45:72-89. [PMID: 11754580 DOI: 10.1021/jm0101141] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [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: 11/29/2022]
Abstract
Structure and energetics of the Src Src Homology 2 (SH2) domain binding with the recognition phosphopeptide pYEEI and its mutants are studied by a hierarchical computational approach. The proposed structure prediction strategy includes equilibrium sampling of the peptide conformational space by simulated tempering dynamics with the simplified, knowledge-based energy function, followed by structural clustering of the resulting conformations and binding free energy evaluation of a single representative from each cluster, a cluster center. This protocol is robust in rapid screening of low-energy conformations and recovers the crystal structure of the pYEEI peptide. Thermodynamics of the peptide-SH2 domain binding is analyzed by computing the average energy contributions over conformations from the clusters, structurally similar to the predicted peptide bound structure. Using this approach, the binding thermodynamics for a panel of studied peptides is predicted in a better agreement with the experiment than previously suggested models. However, the overall correlation between computed and experimental binding affinity remains rather modest. The results of this study show that small differences in binding free energies between the Ala and Gly mutants of the pYEEI peptide are considerably more difficult to predict than the structure of the bound peptides, indicating that accurate computational prediction of binding affinities still remains a major methodological and technical challenge.
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Affiliation(s)
- Gennady M Verkhivker
- Agouron Pharmaceuticals, Inc., A Pfizer Company, 10777 Science Center Drive, San Diego, California 92121-1111, USA.
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Verkhivker GM, Bouzida D, Gehlhaar DK, Rejto PA, Schaffer L, Arthurs S, Colson AB, Freer ST, Larson V, Luty BA, Marrone T, Rose PW. Hierarchy of simulation models in predicting molecular recognition mechanisms from the binding energy landscapes: structural analysis of the peptide complexes with SH2 domains. Proteins 2001; 45:456-70. [PMID: 11746693 DOI: 10.1002/prot.10019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [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: 11/09/2022]
Abstract
Computer simulations using the simplified energy function and simulated tempering dynamics have accurately determined the native structure of the pYVPML, SVLpYTAVQPNE, and SPGEpYVNIEF peptides in the complexes with SH2 domains. Structural and equilibrium aspects of the peptide binding with SH2 domains have been studied by generating temperature-dependent binding free energy landscapes. Once some native peptide-SH2 domain contacts are constrained, the underlying binding free energy profile has the funnel-like shape that leads to a rapid and consistent acquisition of the native structure. The dominant native topology of the peptide-SH2 domain complexes represents an extended peptide conformation with strong specific interactions in the phosphotyrosine pocket and hydrophobic interactions of the peptide residues C-terminal to the pTyr group. The topological features of the peptide-protein interface are primarily determined by the thermodynamically stable phosphotyrosyl group. A diversity of structurally different binding orientations has been observed for the amino-terminal residues to the phosphotyrosine. The dominant native topology for the peptide residues carboxy-terminal to the phosphotyrosine is tolerant to flexibility in this region of the peptide-SH2 domain interface observed in equilibrium simulations. The energy landscape analysis has revealed a broad, entropically favorable topology of the native binding mode for the bound peptides, which is robust to structural perturbations. This could provide an additional positive mechanism underlying tolerance of the SH2 domains to hydrophobic conservative substitutions in the peptide specificity region.
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Affiliation(s)
- G M Verkhivker
- Agouron Pharmaceuticals, Inc., San Diego, California 92121-1111, USA.
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Sloth Andersen A, Hertz Hansen P, Schaffer L, Kristensen C. A new secreted insect protein belonging to the immunoglobulin superfamily binds insulin and related peptides and inhibits their activities. J Biol Chem 2000; 275:16948-53. [PMID: 10748036 DOI: 10.1074/jbc.m001578200] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [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: 11/06/2022] Open
Abstract
Insulin and related peptides are key hormones for the regulation of growth and metabolism. Here we describe a novel high affinity insulin-related peptide-binding protein (IBP) secreted from cells of the insect Spodoptera frugiperda. This IBP is composed of two Ig-like C2 domains, has a molecular mass of 27 kDa, binds human insulin with an affinity of 70 pm, and inhibits insulin signaling through the insulin receptor. The binding protein also binds insulin-like growth factors I and II, proinsulin, mini-proinsulin, and an insulin analog lacking the last 8 amino acids of the B-chain (des-octa peptide insulin) with high affinity, whereas an insulin analog with a Asp-B10 mutation bound with only 1% of the affinity of human insulin. This binding profile suggests that IBP recognizes a region that is highly conserved in the insulin superfamily but distinct from the classical insulin receptor binding site. The closest homologue of the Spodoptera frugiperda binding protein is the essential gene product IMP-L2, found in Drosophila, where it is implicated in neural and ectodermal development (Garbe, J. C., Yang, E., and Fristrom, J. W. (1993) Development 119, 1237-1250). Here we show that the IMP-L2 protein also binds insulin and related peptides, offering a possible functional explanation to the IMP-L2 null lethality.
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Abstract
We present a computational approach for predicting structures of ligand-protein complexes and analyzing binding energy landscapes that combines Monte Carlo simulated annealing technique to determine the ligand bound conformation with the dead-end elimination algorithm for side-chain optimization of the protein active site residues. Flexible ligand docking and optimization of mobile protein side-chains have been performed to predict structural effects in the V32I/I47V/V82I HIV-1 protease mutant bound with the SB203386 ligand and in the V82A HIV-1 protease mutant bound with the A77003 ligand. The computational structure predictions are consistent with the crystal structures of these ligand-protein complexes. The emerging relationships between ligand docking and side-chain optimization of the active site residues are rationalized based on the analysis of the ligand-protein binding energy landscape.
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Affiliation(s)
- L Schaffer
- Agouron Pharmaceuticals, Inc., La Jolla, California 92037, USA
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Mynarcik DC, Williams PF, Schaffer L, Yu GQ, Whittaker J. Identification of common ligand binding determinants of the insulin and insulin-like growth factor 1 receptors. Insights into mechanisms of ligand binding. J Biol Chem 1997; 272:18650-5. [PMID: 9228034 DOI: 10.1074/jbc.272.30.18650] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Insulin and insulin-like growth factor 1 (IGF-1) are peptides that share nearly 50% sequence homology. However, although their cognate receptors also exhibit significant overall sequence homology, the affinity of each peptide for the non-cognate receptor is 2-3 orders of magnitude lower than for the cognate receptor. The molecular basis for this discrimination is unclear, as are the molecular mechanisms underlying ligand binding. We have recently identified a major ligand binding site of the insulin receptor by alanine scannning mutagenesis. These studies revealed that a number of amino acids critical for insulin binding are conserved in the IGF-1 receptor, suggesting that they may play a role in ligand binding. We therefore performed alanine mutagenesis of these amino acids to determine whether this is the case. cDNAs encoding alanine-substituted secreted recombinant IGF-1 receptors were expressed in 293 EBNA cells, and the ligand binding properties of the expressed proteins were evaluated. Mutation of Phe701 resulted in a receptor with undetectable IGF-1 binding; alanine substitution of the corresponding amino acid of the insulin receptor, Phe714, produces a 140-fold reduction in affinity for insulin. Mutation of Asp8, Asn11, Phe58, Phe692, Glu693, His697, and Asn698 produces a 3.5-6-fold reduction in affinity for IGF-1. In contrast, alanine mutation of the corresponding amino acids of the insulin receptor with the exception of Asp12 produces reductions in affinity that are 50-fold or greater. The affinity of insulin for these mutants relative to wild type receptor was similar to that of their relative affinity for IGF-1 with two exceptions; the IC50 values for insulin binding to the mutants of Arg10, which has normal affinity for IGF-1, and His697, which has a 6-fold reduction in affinity for IGF-1, were both at least 2 orders of magnitude greater than for wild type receptor. The Kd values for insulin of the corresponding alanine mutants of the insulin receptor, Arg14 and His710, are 2-3 orders of magnitude greater than for wild type receptor. However, in contrast, the relative affinity of des(25-30)[PheB25 alpha-carboxamide]insulin for these IGF-1 receptor mutants is reduced only 4- and 50-fold, respectively.
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Affiliation(s)
- D C Mynarcik
- Department of Medicine, State University of New York at Stony Brook, Stony Brook, New York 11794, USA
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Mynarcik DC, Williams PF, Schaffer L, Yu GQ, Whittaker J. Analog binding properties of insulin receptor mutants. Identification of amino acids interacting with the COOH terminus of the B-chain of the insulin molecule. J Biol Chem 1997; 272:2077-81. [PMID: 8999905 DOI: 10.1074/jbc.272.4.2077] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [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] [Indexed: 02/03/2023] Open
Abstract
Recent studies utilizing alanine scanning mutagenesis have identified a major ligand binding domain of the secreted recombinant insulin receptor composed of two subdomains, one between amino acids 1 and 120 and the other between amino acids 704 and 716. In order to obtain a more detailed characterization of these subdomains, we examined the binding of an insulin superanalog, des-(B25-30)-[His-A8, Asp-B10, Tyr-B25 alpha-carboxamide]insulin, to alanine mutants of the ligand binding determinants of these subdomains. cDNAs encoding mutant secreted recombinant receptors were transiently expressed in 293 EBNA cells, and the binding properties for this analog of the expressed receptors were evaluated. In general des-(B25-30)-[His-A8, Asp-B10, Tyr-B25 alpha-carboxamide]insulin binding correlated with insulin binding, suggesting that both peptides bound to the receptor in a similar manner. Alanine mutations of eight amino acids (Asn15, Phe64, Phe705, Glu706, Tyr708, Leu709, Asn711, and Phe714) of the receptor produced the most profound decreases in affinity for des-(B25-30)-[His-A8, Asp-B10, Tyr-B25 alpha-carboxamide]insulin, suggesting that interactions with these amino acids contributed the major part of the free energy of the ligand-receptor interaction. Mutation of Arg14 and His710 to Ala produced receptors with undetectable insulin binding but an affinity for des-(B25-30)-[His-A8, Asp-B10, Tyr-B25 alpha-carboxamide]insulin only 8-23-fold less than for native receptor. Further analog studies were performed to elucidate this paradox. The receptor binding potencies of His-A8 and Asp-B10 insulins for these receptor mutants appeared to parallel their relative potencies for native receptor. In contrast the receptor binding potency of des-(B25-30)-[Tyr-B25 alpha-carboxamide]insulin was disproportionately increased for these mutants when compared with its potency for native receptor.
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Affiliation(s)
- D C Mynarcik
- Department of Medicine and Physiology, State University of New York at Stony Brook, Stony Brook, New York 11794, USA
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Sax F, Hartman G, Egbertson M, Lynch J, Schaffer L, Cook J, Gould R. MK-0383, a potent intravenous inhibitor of platelet GP IIb/IIIa. Atherosclerosis 1994. [DOI: 10.1016/0021-9150(94)94410-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
We examined the ability of intravenous (i.v.) challenge with pentagastrin to induce behavioural and cardiovascular effects consistent with panic attack in conscious rhesus monkeys. For behavioural evaluation, 4 naive male rhesus monkeys familiar with minimal manual restraint necessary for drug administration received a rapid i.v. bolus of pentagastrin (4, 8 or 16 micrograms/kg) or water on four separate occasions according to a randomised cross-over design. Behaviour was rated by a blind observer continuously during, and for the first 5 min immediately following i.v. injections while the monkey sat on the handler's lap, and then for a further 25 min in an individual observation cage. In separate experiments, the ability of pentagastrin to alter cardiovascular parameters which may accompany panic or anxiety (elevated heart rate and blood pressure) was explored. For cardiovascular studies, 8 male or female rhesus monkeys with femoral artery catheters were chair restrained and received a bolus injection of pentagastrin (4, 8 or 16 micrograms/kg) or saline into the saphenous vein at 30 min intervals. Blood pressure and heart rate were monitored continuously using a Statham Gould pressure transducer. Pentagastrin induced no consistent behavioural or cardiovascular changes. Similar pilot studies using CCK4 also failed to reveal such effects. We conclude that CCK-induced panic-like effects may not be demonstrable following challenge with pentagastrin under laboratory conditions in rhesus monkeys.
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Affiliation(s)
- N M Rupniak
- Merck Sharp and Dohme Research Laboratories, Neuroscience Research Centre, Harlow, Essex, UK
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Cook JJ, Niewiarowski S, Yan Z, Schaffer L, Lu W, Stewart GJ, Mosser DM, Myers JA, Maione TE. Platelet factor 4 efficiently reverses heparin anticoagulation in the rat without adverse effects of heparin-protamine complexes. Circulation 1992; 85:1102-9. [PMID: 1537108 DOI: 10.1161/01.cir.85.3.1102] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND It has been observed that the reversal of heparin anticoagulation in humans by protamine sulfate (PS) results in various adverse reactions including leukopenia, thrombocytopenia, activation of complement, increased vascular permeability, systemic hypotension, pulmonary vasoconstriction, and pulmonary edema. The purpose of this study was to compare the efficacy and effects of native platelet factor 4 (PF4) and recombinant platelet factor 4 (rPF4) with those of PS in heparin neutralization in vivo, using a rat model. METHODS AND RESULTS Sprague-Dawley rats were anesthetized with sodium pentobarbital, and the right femoral vein and carotid artery were cannulated. For determination of activated partial thromboplastin time, platelet count, white blood cell count, and complement titer, arterial blood samples were taken before and immediately after heparin (10 units/100 g) infusion and at several time points after the infusion of the neutralizing agent (PS, 0.1 mg/100 g; PF4, 0.5 mg/100 g). In separate groups of animals, mean arterial blood pressure was monitored throughout identical protocols and the lungs were prepared for histological examination. The anticoagulant activity of heparin was effectively reversed by all of the neutralizing agents (PS, PF4, and rPF4). Platelet count (48% of initial), white blood cell count (52% of initial), complement titer (60% of initial), and mean arterial pressure (20% decrease) decreased significantly in heparinized animals receiving PS but not in those receiving PF4 or rPF4. Lung interstitium appeared normal when heparin was followed by PF4; however, interstitial edema and hemorrhage were observed with heparin-PS. CONCLUSIONS These results suggest that PF4 efficiently reverses heparin anticoagulation in the rat without the adverse effects of heparin-protamine complexes. Therefore, rPF4 may be an appropriate substitute for PS in patients undergoing cardiovascular surgery and other procedures that require heparin anticoagulation.
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Affiliation(s)
- J J Cook
- Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140
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Mumford RA, Williams H, Mao J, Dahlgren ME, Frankenfield D, Nolan T, Schaffer L, Doherty JB, Fletcher D, Hand K. Direct assay of A alpha(1-21), a PMN elastase-specific cleavage product of fibrinogen, in the chimpanzee. Ann N Y Acad Sci 1991; 624:167-78. [PMID: 2064218 DOI: 10.1111/j.1749-6632.1991.tb17016.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- R A Mumford
- Department of Immunology & Inflammation, Merck Sharp & Dohme Research Laboratories, Rahway, New Jersey 07065
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Nutt EM, Jain D, Lenny AB, Schaffer L, Siegl PK, Dunwiddie CT. Purification and characterization of recombinant antistasin: a leech-derived inhibitor of coagulation factor Xa. Arch Biochem Biophys 1991; 285:37-44. [PMID: 1990979 DOI: 10.1016/0003-9861(91)90325-d] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Antistasin (ATS) is a selective, tight-binding inhibitor of blood coagulation Factor Xa originally isolated from the salivary glands of the Mexican leech Haementeria officinalis. In order to provide sufficient quantities of ATS to further investigate the role of Factor Xa in blood coagulation, a recombinant version of ATS has been produced in an insect baculovirus host-vector system. In this study, we describe the purification and in vitro and in vivo characterization of a single recombinant antistasin (rATS) isoform. The purified protein constitutes a minor isoform relative to the more abundant ATS isoforms present in leech salivary gland extracts. In vitro, rATS inhibits purified human Factor Xa stoichiometrically, prolongs plasma-based clotting assays at nanomolar concentrations, and like native ATS, is cleaved at a single position by Factor Xa during the course of inhibition. An initial evaluation of the in vivo efficacy of rATS was addressed utilizing a rhesus monkey model of mild disseminated intravascular coagulation. rATS was shown to fully suppress thromboplastin-induced fibrinopeptide A generation in a dose-dependent fashion. The availability of rATS should provide a valuable tool for the critical evaluation of the specific role played by Factor Xa in coagulation.
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Affiliation(s)
- E M Nutt
- Department of Biological Chemistry, Merck Sharp & Dohme Research Laboratories, West Point, Pennsylvania 19486
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Abstract
Depressed inpatients have a DST non-suppression rate that is several times greater than that of depressed outpatients. To explore what clinical features of depression might explain this difference, 25 depressed inpatients who were DST non-suppressors were compared with 16 DST suppressors, using 70 clinical variables. Those variables that were different between these two groups of inpatients were then used to compare depressed inpatients and outpatients. Three variables that were significantly associated with DST status in depressed inpatients were also found to differentiate between depressed inpatients and depressed outpatients. DST suppression was associated with a family history of alcoholism, with the symptom hypersomnia, and with a younger age at index interview.
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Affiliation(s)
- M J Garvey
- Department of Psychiatry, VA Medical Center, Iowa City, IA 52240
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Pendleton RG, Bendesky RJ, Schaffer L, Nolan TE, Gould RJ, Clineschmidt BV. Roles of endogenous cholecystokinin in biliary, pancreatic and gastric function: studies with L-364,718, a specific cholecystokinin receptor antagonist. J Pharmacol Exp Ther 1987; 241:110-6. [PMID: 2437283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A new, highly potent antagonist of gut cholecystokinin (CCK) receptors has been examined for effects upon postprandial biliary and exocrine pancreatic secretion in conscious dogs with chronic duodenal pouches. This drug (L-364,718) markedly inhibited the postprandial increases in biliary volume, bile acid and bilirubin secretion. However, even at high p.o. doses relative to its ability to antagonize the effects of exogenous CCK, no effects were observed upon the pancreatic secretion of either fluid volume or amylase and lipase under similar conditions. In additional studies, pretreatment with L-364,718 did not significantly reverse the inhibitory effects of a fatty acid salt (sodium oleate) upon gastric emptying in gastric fistula dogs. Moreover, pretreatment with L-364,718 had no significant effects upon postprandial acid and pepsin secretion in lesser curvature (vagally innervated) pouch dogs or did it affect basal (interdigestive) gastric secretion in rats. These results suggest that endogenous CCK plays a critical physiological role in regulating postprandial biliary outflow, but not pancreatic enzyme secretion or the gastric emptying of at least liquid fatty substances. The latter two findings stand in contrast with classical views regarding the physiological function(s) of this hormone.
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Siqueira EB, Kranzler LI, Schaffer L. Compression of the spinal cord by paraffin. South Med J 1985; 78:1525-6. [PMID: 4071190 DOI: 10.1097/00007611-198512000-00036] [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] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Abstract
Three cases of glioblastoma multiforme are presented. These cases have in common the fact that all three patients were relatives but not blood relatives. There had been prolonged intimate contact between them before the development of the neoplastic lesion.
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