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Hawkes LA, Davies P, Hall AE, Horton TW, Stamp T, Witt MJ, Sheehan EV. People behind the "pings"; limiting authorship threatens collaboration in telemetry. J Fish Biol 2024. [PMID: 38519854 DOI: 10.1111/jfb.15700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 02/09/2024] [Indexed: 03/25/2024]
Affiliation(s)
- L A Hawkes
- Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - P Davies
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
| | - A E Hall
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
| | - T W Horton
- Faculty of Environment, Society and Economy, University of Exeter, Penryn Campus, Penryn, UK
| | - T Stamp
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
| | - M J Witt
- Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
- Faculty of Environment, Society and Economy, University of Exeter, Penryn Campus, Penryn, UK
| | - E V Sheehan
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
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2
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Edwards B, Dowinton O, Hall AE, Murgatroyd PAE, Buchberger S, Antonelli T, Siemann GR, Rajan A, Morales EA, Zivanovic A, Bigi C, Belosludov RV, Polley CM, Carbone D, Mayoh DA, Balakrishnan G, Bahramy MS, King PDC. Giant valley-Zeeman coupling in the surface layer of an intercalated transition metal dichalcogenide. Nat Mater 2023; 22:459-465. [PMID: 36658327 DOI: 10.1038/s41563-022-01459-z] [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] [Received: 07/04/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Spin-valley locking is ubiquitous among transition metal dichalcogenides with local or global inversion asymmetry, in turn stabilizing properties such as Ising superconductivity, and opening routes towards 'valleytronics'. The underlying valley-spin splitting is set by spin-orbit coupling but can be tuned via the application of external magnetic fields or through proximity coupling. However, only modest changes have been realized to date. Here, we investigate the electronic structure of the V-intercalated transition metal dichalcogenide V1/3NbS2 using microscopic-area spatially resolved and angle-resolved photoemission spectroscopy. Our measurements and corresponding density functional theory calculations reveal that the bulk magnetic order induces a giant valley-selective Ising coupling exceeding 50 meV in the surface NbS2 layer, equivalent to application of a ~250 T magnetic field. This energy scale is of comparable magnitude to the intrinsic spin-orbit splittings, and indicates how coupling of local magnetic moments to itinerant states of a transition metal dichalcogenide monolayer provides a powerful route to controlling their valley-spin splittings.
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Affiliation(s)
- B Edwards
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - O Dowinton
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
| | - A E Hall
- Department of Physics, University of Warwick, Coventry, United Kingdom
| | - P A E Murgatroyd
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - S Buchberger
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - T Antonelli
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - G-R Siemann
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - A Rajan
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - E Abarca Morales
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - A Zivanovic
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - C Bigi
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
| | - R V Belosludov
- Institute for Materials Research, Tohoku University, Sendai, Japan
| | - C M Polley
- MAX IV Laboratory, Lund University, Lund, Sweden
| | - D Carbone
- MAX IV Laboratory, Lund University, Lund, Sweden
| | - D A Mayoh
- Department of Physics, University of Warwick, Coventry, United Kingdom
| | - G Balakrishnan
- Department of Physics, University of Warwick, Coventry, United Kingdom
| | - M S Bahramy
- Department of Physics and Astronomy, University of Manchester, Manchester, UK.
| | - P D C King
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK.
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Hall AE, Brandenburg C, Ward EC, Pokorny MA, Trafford K, Seabrook M, Whitfield BCS. Evaluation of health service outcomes for an audiology first point of contact retrocochlear clinic: a 6-year retrospective cohort study. Int J Audiol 2022:1-9. [DOI: 10.1080/14992027.2022.2073477] [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: 11/05/2022]
Affiliation(s)
- Amber E. Hall
- Speech Pathology and Audiology Department, Logan Hospital, Meadowbrook, Australia
| | - Caitlin Brandenburg
- Centre for Functioning and Health Research, Metro South Health, Brisbane, Australia
| | - Elizabeth C. Ward
- Centre for Functioning and Health Research, Metro South Health, Brisbane, Australia
- School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia
| | - Michelle A. Pokorny
- School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia
| | - Katye Trafford
- Speech Pathology and Audiology Department, Logan Hospital, Meadowbrook, Australia
| | - Marnie Seabrook
- Speech Pathology and Audiology Department, Logan Hospital, Meadowbrook, Australia
| | - Bernard C. S. Whitfield
- Integrated Specialist ENT Service, Department of Otolaryngology Head and Neck Surgery, Logan Hospital, Meadowbrook, Australia
- School of Medicine, Griffith University, Southport, Australia
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4
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Jiao M, Hall AE, Nolte L, Piper A, Lisy K, Jefford M. A rapid review of needs assessment tools for post-treatment cancer survivors. Eur J Cancer Care (Engl) 2017; 27:e12764. [PMID: 28921739 DOI: 10.1111/ecc.12764] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/03/2017] [Indexed: 11/27/2022]
Abstract
Relevant, comprehensive and psychometrically rigorous needs assessment tools are needed to ensure appropriate care is delivered to cancer survivors who have completed treatment. The aim of this rapid review was to identify and describe needs assessment tools that are used in cancer survivors post-treatment, assess their psychometric properties and describe their use in clinical care. The electronic databases Medline, Cochrane Library, CINAHL and PsycINFO were searched. Six studies were identified that described five needs assessment tools used in cancer survivors post-treatment. None of these tools covered all domains of unmet need nor demonstrated adequate evidence of all recommended criteria of validity and reliability. Few had been evaluated for use in a clinical environment. Out of the five tools, the Survivor Unmet Needs Survey (SUNS) showed the strongest psychometric properties. There is little empirical evidence available to guide recommendations on the most appropriate process of conducting needs assessment with cancer survivors once they have completed treatment.
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Affiliation(s)
- M Jiao
- Australian Cancer Survivorship Centre, A Richard Pratt legacy, Victorian Comprehensive Cancer Centre, Melbourne, Vict., Australia.,Pharmacy Department, Victorian Comprehensive Cancer Centre, Melbourne, Vict., Australia
| | - A E Hall
- Priority Research Centre for Health Behaviour, Faculty of Health, The University of Newcastle, Callaghan, NSW, Australia.,Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
| | - L Nolte
- The Advance Care Planning Department, Austin Health, Heidelberg, Vict., Australia
| | - A Piper
- Australian Cancer Survivorship Centre, A Richard Pratt legacy, Victorian Comprehensive Cancer Centre, Melbourne, Vict., Australia
| | - K Lisy
- Department of Cancer Experiences Research, Victorian Comprehensive Cancer Centre, Melbourne, Vict., Australia
| | - M Jefford
- Australian Cancer Survivorship Centre, A Richard Pratt legacy, Victorian Comprehensive Cancer Centre, Melbourne, Vict., Australia.,Department of Cancer Experiences Research, Victorian Comprehensive Cancer Centre, Melbourne, Vict., Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Vict., Australia
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5
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Hall AE, Lu WT, Godfrey JD, Antonov AV, Paicu C, Moxon S, Dalmay T, Wilczynska A, Muller PAJ, Bushell M. The cytoskeleton adaptor protein ankyrin-1 is upregulated by p53 following DNA damage and alters cell migration. Cell Death Dis 2016; 7:e2184. [PMID: 27054339 PMCID: PMC4855670 DOI: 10.1038/cddis.2016.91] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [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: 12/11/2015] [Revised: 03/09/2016] [Accepted: 03/15/2016] [Indexed: 12/19/2022]
Abstract
The integrity of the genome is maintained by a host of surveillance and repair mechanisms that are pivotal for cellular function. The tumour suppressor protein p53 is a major component of the DNA damage response pathway and plays a vital role in the maintenance of cell-cycle checkpoints. Here we show that a microRNA, miR-486, and its host gene ankyrin-1 (ANK1) are induced by p53 following DNA damage. Strikingly, the cytoskeleton adaptor protein ankyrin-1 was induced over 80-fold following DNA damage. ANK1 is upregulated in response to a variety of DNA damage agents in a range of cell types. We demonstrate that miR-486-5p is involved in controlling G1/S transition following DNA damage, whereas the induction of the ankyrin-1 protein alters the structure of the actin cytoskeleton and sustains limited cell migration during DNA damage. Importantly, we found that higher ANK1 expression correlates with decreased survival in cancer patients. Thus, these observations highlight ANK1 as an important effector downstream of the p53 pathway.
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Affiliation(s)
- A E Hall
- Medical Research Council (MRC), Toxicology Unit, Leicester, UK
| | - W-T Lu
- Medical Research Council (MRC), Toxicology Unit, Leicester, UK
| | - J D Godfrey
- Medical Research Council (MRC), Toxicology Unit, Leicester, UK
| | - A V Antonov
- Medical Research Council (MRC), Toxicology Unit, Leicester, UK
| | - C Paicu
- The Genome Analysis Centre, Norwich, UK.,School of Computing Sciences, University of East Anglia, Norwich, UK
| | - S Moxon
- The Genome Analysis Centre, Norwich, UK
| | - T Dalmay
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - A Wilczynska
- Medical Research Council (MRC), Toxicology Unit, Leicester, UK
| | - P A J Muller
- Medical Research Council (MRC), Toxicology Unit, Leicester, UK
| | - M Bushell
- Medical Research Council (MRC), Toxicology Unit, Leicester, UK
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6
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Mackenzie LJ, Carey ML, Sanson-Fisher RW, D'Este CA, Hall AE. Cancer patients' willingness to answer survey questions about life expectancy. Support Care Cancer 2012; 20:3335-41. [PMID: 22576980 PMCID: PMC3480580 DOI: 10.1007/s00520-012-1477-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 04/16/2012] [Indexed: 11/29/2022]
Abstract
Purpose This study aimed to determine the proportion and characteristics of radiation oncology outpatients who were willing to answer questions about their life expectancy. Methods A cross-sectional patient self-report survey was conducted using touch screen computers in Australian radiation oncology treatment centers. The primary outcome was the respondent’s willingness to complete a survey subsection about life expectancy. Demographic and disease characteristics were also collected, and level of anxiety and depression was assessed using the Hospital Anxiety and Depression Scale. Results Of the 469 oncology outpatients who completed the survey, 327 (70 %; 95 % CI, 65 %, 74 %) indicated that they were willing to answer questions about life expectancy. Being female (p < 0.001), older (p < 0.05), born in Asia (p < 0.05), and being diagnosed with cancer types other than breast and prostate cancer (p < 0.01) were associated with lower odds of answering life expectancy questions. Conclusions The opportunity to opt-out of survey questions about sensitive issues such as life expectancy is a feasible method for accessing important information about patient preferences while minimizing burden. Further research may be needed to improve acceptability of life expectancy research to some patient groups.
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Affiliation(s)
- L J Mackenzie
- Priority Research Centre for Health Behaviour, School of Medicine and Public Health, Faculty of Health, University of Newcastle, Callaghan, New South Wales 2308, Australia.
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7
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Abstract
Solutions have been computed for the point polarization of an infinite cable-like membrane obeying the equations used to reproduce the Purkinje fiber action potential (Noble, 1960, 1962a) in order to determine the conditions for initiating all-or-nothing repolarization during the action potential plateau. It was found that all-or-nothing repolarization would not be obtainable during the first half of the action potential in spite of the fact that the membrane current-voltage relations contain regions of negative conductance. At the point at which the all-or-nothing response is first obtained, the computed threshold is large and repolarization almost back to the resting potential would be required in order to initiate the response. The results are discussed in relation to the experimental evidence at present available on repolarization in heart muscle.
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8
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Abstract
OBJECTIVE While coronary artery disease (CAD) is associated with disturbances of the plasma fibrinolytic system, the nature of these disturbances is not fully defined. Fibrinolysis is regulated by plasmin, whose production is mediated by plasminogen activator conversion of plasminogen (Plg) to plasmin. The cascade is modulated by feedback loops that include Plg activator inhibitor 1 (PAI-1). Molecular interactions with Plg kringle domains play an important role in regulating plasmin production and its modulation of fibrinolysis. We hypothesized that interactions of tissue plasminogen activator (tPA) with Plg kringle domains regulates plasmin levels in patients with stable CAD. METHODS Plasma was collected from patients (n = 33) with an angiographically significant CAD and controls (n = 18) with angiographically established normal or minimally diseased arteries. Plasmin activity, tPA activity, and plasma levels of Plg, PAI-1, uPA, and tPA were determined. RESULTS CAD patients had 1.7-fold greater plasmin activity (P = 0.02) that correlated with 1.5-fold higher tPA activity when compared to controls. Epitope mapping of Plg domains showed Plg differences in epitope exposure between the two groups. Plasma from CAD patients had 50% less (P < 0.001) detectable kringle 4 and 48% less (P = 0.007) detectable kringles 1-3. CONCLUSIONS Based on detectable differences in Plg, we conclude that in patients with stable CAD, Plg complexed with tPA exists in a conformation that enables increased tPA activity and Plg conversion to plasmin.
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Affiliation(s)
- M C Drinane
- Department of Surgery, Vascular Section, Dartmouth Medical School, Lebanon, NH 03756, USA
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9
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Ouédraogo JT, Gowda BS, Jean M, Close TJ, Ehlers JD, Hall AE, Gillaspie AG, Roberts PA, Ismail AM, Bruening G, Gepts P, Timko MP, Belzile FJ. An improved genetic linkage map for cowpea (Vigna unguiculata L.) combining AFLP, RFLP, RAPD, biochemical markers, and biological resistance traits. Genome 2002; 45:175-88. [PMID: 11908660 DOI: 10.1139/g01-102] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.2] [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: 11/22/2022]
Abstract
An improved genetic linkage map has been constructed for cowpea (Vigna unguiculata L. Walp.) based on the segregation of various molecular markers and biological resistance traits in a population of 94 recombinant inbred lines (RILs) derived from the cross between 'IT84S-2049' and '524B'. A set of 242 molecular markers, mostly amplified fragment length polymorphism (AFLP), linked to 17 biological resistance traits, resistance genes, and resistance gene analogs (RGAs) were scored for segregation within the parental and recombinant inbred lines. These data were used in conjunction with the 181 random amplified polymorphic DNA (RAPD), restriction fragment length polymorphism (RFLP), AFLP, and biochemical markers previously mapped to construct an integrated linkage map for cowpea. The new genetic map of cowpea consists of 11 linkage groups (LGs) spanning a total of 2670 cM, with an average distance of 6.43 cM between markers. Astonishingly, a large, contiguous portion of LG1 that had been undetected in previous mapping work was discovered. This region, spanning about 580 cM, is composed entirely of AFLP markers (54 in total). In addition to the construction of a new map, molecular markers associated with various biological resistance and (or) tolerance traits, resistance genes, and RGAs were also placed on the map, including markers for resistance to Striga gesnerioides races 1 and 3, CPMV, CPSMV, B1CMV, SBMV, Fusarium wilt, and root-knot nematodes. These markers will be useful for the development of tools for marker-assisted selection in cowpea breeding, as well as for subsequent map-based cloning of the various resistance genes.
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Affiliation(s)
- J T Ouédraogo
- Institut de l'Environnement et de Recherches Agricoles (INERA), Ouagadougou, Burkina Faso
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10
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Hall AE, Findell JL, Schaller GE, Sisler EC, Bleecker AB. Ethylene perception by the ERS1 protein in Arabidopsis. Plant Physiol 2000; 123:1449-58. [PMID: 10938361 PMCID: PMC59101 DOI: 10.1104/pp.123.4.1449] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/1999] [Accepted: 04/05/2000] [Indexed: 05/20/2023]
Abstract
Ethylene perception in Arabidopsis is controlled by a family of five genes, including ETR1, ERS1 (ethylene response sensor 1), ERS2, ETR2, and EIN4. ERS1, the most highly conserved gene with ETR1, encodes a protein with 67% identity to ETR1. To clarify the role of ERS1 in ethylene sensing, we biochemically characterized the ERS1 protein by heterologous expression in yeast. ERS1, like ETR1, forms a membrane-associated, disulfide-linked dimer. In addition, yeast expressing the ERS1 protein contains ethylene-binding sites, indicating ERS1 is also an ethylene-binding protein. This finding supports previous genetic evidence that isoforms of ETR1 also function in plants as ethylene receptors. Further, we used the ethylene antagonist 1-methylcyclopropene (1-MCP) to characterize the ethylene-binding sites of ERS1 and ETR1. We found 1-MCP to be both a potent inhibitor of the ethylene-induced seedling triple response, as well as ethylene binding by yeast expressing ETR1 and ERS1. Yeast expressing ETR1 and ERS1 showed nearly identical sensitivity to 1-MCP, suggesting that the ethylene-binding sites of ETR1 and ERS1 have similar affinities for ethylene.
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Affiliation(s)
- A E Hall
- Department of Botany, University of Wisconsin, Madison, Wisconsin 53706, USA
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11
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Ismail AM, Hall AE, Close TJ. Allelic variation of a dehydrin gene cosegregates with chilling tolerance during seedling emergence. Proc Natl Acad Sci U S A 1999; 96:13566-70. [PMID: 10557361 PMCID: PMC23988 DOI: 10.1073/pnas.96.23.13566] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dehydrins (DHNs, LEA D-11) are plant proteins present during environmental stresses associated with dehydration or low temperatures and during seed maturation. Functions of DHNs have not yet been defined. Earlier, we hypothesized that a approximately 35-kDa DHN and membrane properties that reduce electrolyte leakage from seeds confer chilling tolerance during seedling emergence of cowpea (Vigna unguiculata L. Walp.) in an additive and independent manner. Evidence for this hypothesis was not rigorous because it was based on correlations of presence/absence of the DHN and slow electrolyte leakage with chilling tolerance in closely related cowpea lines that have some other genetic differences. Here, we provide more compelling genetic evidence for involvement of the DHN in chilling tolerance of cowpea. We developed near-isogenic lines by backcrossing. We isolated and determined the sequence of a cDNA corresponding to the approximately 35-kDa DHN and used gene-specific oligonucleotides derived from it to test the genetic linkage between the DHN presence/absence trait and the DHN structural gene. We tested for association between the DHN presence/absence trait and both low-temperature seed emergence and electrolyte leakage. We show that allelic differences in the Dhn structural gene map to the same position as the DHN protein presence/absence trait and that the presence of the approximately 35-kDa DHN is indeed associated with chilling tolerance during seedling emergence, independent of electrolyte leakage effects. Two types of allelic variation in the Dhn gene were identified in the protein-coding region, deletion of one Phi-segment from the DHN-negative lines and two single amino acid substitutions.
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Affiliation(s)
- A M Ismail
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521-0124, USA
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12
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Hall AE, Chen QG, Findell JL, Schaller GE, Bleecker AB. The relationship between ethylene binding and dominant insensitivity conferred by mutant forms of the ETR1 ethylene receptor. Plant Physiol 1999; 121:291-300. [PMID: 10482685 PMCID: PMC59379 DOI: 10.1104/pp.121.1.291] [Citation(s) in RCA: 56] [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] [Subscribe] [Scholar Register] [Received: 03/30/1999] [Accepted: 06/06/1999] [Indexed: 05/17/2023]
Abstract
Ethylene responses in Arabidopsis are mediated by a small family of receptors, including the ETR1 gene product. Specific mutations in the N-terminal ethylene-binding domain of any family member lead to dominant ethylene insensitivity. To investigate the mechanism of ethylene insensitivity, we examined the effects of mutations on the ethylene-binding activity of the ETR1 protein expressed in yeast. The etr1-1 and etr1-4 mutations completely eliminated ethylene binding, while the etr1-3 mutation severely reduced binding. Additional site-directed mutations that disrupted ethylene binding in yeast also conferred dominant ethylene insensitivity when the mutated genes were transferred into wild-type Arabidopsis plants. By contrast, the etr1-2 mutation did not disrupt ethylene binding in yeast. These results indicate that dominant ethylene insensitivity may be conferred by mutations that disrupt ethylene binding or that uncouple ethylene binding from signal output by the receptor. Increased dosage of wild-type alleles in triploid lines led to the partial recovery of ethylene sensitivity, indicating that dominant ethylene insensitivity may involve either interactions between wild-type and mutant receptors or competition between mutant and wild-type receptors for downstream effectors.
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Affiliation(s)
- A E Hall
- Department of Botany, University of Wisconsin, Madison, Wisconsin 53706, USA
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13
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Ismail AM, Hall AE, Close TJ. Purification and partial characterization of a dehydrin involved in chilling tolerance during seedling emergence of cowpea. Plant Physiol 1999; 120:237-44. [PMID: 10318701 PMCID: PMC59256 DOI: 10.1104/pp.120.1.237] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/1998] [Accepted: 01/15/1999] [Indexed: 05/18/2023]
Abstract
Dehydrins are a family of proteins (LEA [late-embryogenesis abundant] D11) commonly induced by environmental stresses associated with low temperature or dehydration and during seed maturation drying. Our previous genetic studies suggested an association of an approximately 35-kD protein (by immunological evidence a dehydrin) with chilling tolerance during emergence of seedlings of cowpea (Vigna unguiculata) line 1393-2-11. In the present study we found that the accumulation of this protein in developing cowpea seeds is coordinated with the start of the dehydration phase of embryo development. We purified this protein from dry seeds of cowpea line 1393-2-11 by using the characteristic high-temperature solubility of dehydrins as an initial enrichment step, which was followed by three chromatography steps involving cation exchange, hydrophobic interaction, and anion exchange. Various characteristics of this protein confirmed that indeed it is a dehydrin, including total amino acid composition, partial amino acid sequencing, and the adoption of alpha-helical structure in the presence of sodium dodecyl sulfate. The propensity of dehydrins to adopt alpha-helical structure in the presence of sodium dodecyl sulfate, together with the apparent polypeptide adhesion property of this cowpea dehydrin, suggests a role in stabilizing other proteins or membranes. Taken together, the genetic, physiological, and physicochemical data are at this stage consistent with a cause-and-effect relationship between the presence in mature seeds of the approximately 35-kD dehydrin, which is the product of a single member of a multigene family, and an increment of chilling tolerance during emergence of cowpea seedlings.
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Affiliation(s)
- A M Ismail
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521-0124, USA
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14
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Mount DB, Baekgaard A, Hall AE, Plata C, Xu J, Beier DR, Gamba G, Hebert SC. Isoforms of the Na-K-2Cl cotransporter in murine TAL I. Molecular characterization and intrarenal localization. Am J Physiol 1999; 276:F347-58. [PMID: 10070158 DOI: 10.1152/ajprenal.1999.276.3.f347] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have identified several alternatively spliced cDNAs encoding mBSC1, an apical bumetanide-sensitive Na+-K+-2Cl- cotransporter from mouse kidney. Two full-length clones were isolated, designated C4 and C9, predicting proteins of 770 and 1,095 amino acids, respectively. The C4 isoforms are generated by utilization of an alternative polyadenylation site located within the intron between exons 16 and 17 of the mBSC1 gene on chromosome 2; the resultant transcripts predict a truncated COOH terminus ending in a unique 55 amino acid sequence. The predicted C4 and C9 COOH termini differ in the distribution of putative phosphorylation sites for both protein kinase A and C. Independent splicing events involve three previously described cassette exons, which are predicted to encode most of the second transmembrane domain. A total of six different isoforms are expressed, generated by the combinatorial association of three cassette exons and two alternative 3' ends. C9-specific and C4-specific antibodies detect proteins of approximately 150 and 120 kDa, respectively, in mouse kidney. Immunofluorescence and immunohistochemistry indicate expression of both COOH-terminal isoforms within the thick ascending limb of the loop of Henle (TAL). However, staining with the C4 antibody is more heterogeneous, with a decreased proportion of positive cells in the cortical TAL. Functional expression in Xenopus oocytes indicates a dominant negative function for C4 isoforms [companion study, C. Plata, D. B. Mount, V. Rubio, S. C. Hebert, and G. Gamba. Am. J. Physiol. 276 (Renal Physiol. 45): F347-F358, 1999], and the differential expression of these isoforms may contribute to functional heterogeneity of Na+-K+-2Cl- cotransport in mouse TAL.
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Affiliation(s)
- D B Mount
- Division of Nephrology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA.
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15
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Abstract
The ETR1 receptor from Arabidopsis binds the gaseous hormone ethylene. A copper ion associated with the ethylene-binding domain is required for high-affinity ethylene-binding activity. A missense mutation in the domain that renders the plant insensitive to ethylene eliminates both ethylene binding and the interaction of copper with the receptor. A sequence from the genome of the cyanobacterium Synechocystis sp. strain 6803 that shows homology to the ethylene-binding domain of ETR1 encodes a functional ethylene-binding protein. On the basis of sequence conservation between the Arabidopsis and the cyanobacterial ethylene-binding domains and on in vitro mutagenesis of ETR1, a structural model for this copper-based ethylene sensor domain is presented.
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Affiliation(s)
- F I Rodríguez
- Department of Botany, 430 Lincoln Drive, University of Wisconsin, Madison, WI 53706, USA
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Cheng I, Qureshi I, Chattopadhyay N, Qureshi A, Butters RR, Hall AE, Cima RR, Rogers KV, Hebert SC, Geibel JP, Brown EM, Soybel DI. Expression of an extracellular calcium-sensing receptor in rat stomach. Gastroenterology 1999; 116:118-26. [PMID: 9869609 DOI: 10.1016/s0016-5085(99)70235-0] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Circulating levels of Ca2+ can influence secretory functions and myoelectrical properties of the stomach. A Ca2+-sensing receptor (CaR) has recently been identified in tissues that regulate systemic Ca2+ homeostasis. The aim of this study was to evaluate expression of CaR in the stomach of the rat. METHODS In forestomach and glandular stomach, reverse-transcription polymerase chain reaction was used to amplify a 380-base pair product, which is 99% homologous with transcripts obtained in parathyroid and kidney. RESULTS Northern analysis of gastric mucosal polyA+ RNA revealed 7. 5- and 4.1-kilobase transcripts, similar to those obtained in rat parathyroid and kidney. Immunohistochemistry revealed CaR expression in regions of the submucosal plexus and myenteric neurons. In sections of intact tissue, preparations of primary culture surface cells and surgically dissected gastric glands, staining was observed consistently in epithelial cells of the gastric glands and in gastric surface cells. In parietal cells in isolated gastric glands, intracellular levels of Ca2+ responded to conditions that are known to activate CaR. CONCLUSIONS These are the first reported observations that CaR is expressed in different epithelial cells of mammalian gastric mucosa and its enteric nerve regions. The effects of extracellular Ca2+ on gastric function may be attributable to activation of CaR.
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MESH Headings
- Animals
- Base Sequence
- Blotting, Northern
- Calcium/metabolism
- Cells, Cultured
- DNA, Complementary/genetics
- Extracellular Space/metabolism
- Gastric Mucosa/cytology
- Gastric Mucosa/metabolism
- Immunohistochemistry
- Molecular Sequence Data
- Muscle, Smooth/cytology
- Muscle, Smooth/metabolism
- Parietal Cells, Gastric/metabolism
- RNA/biosynthesis
- RNA/isolation & purification
- Rats
- Rats, Sprague-Dawley
- Receptors, Calcium-Sensing
- Receptors, Cell Surface/biosynthesis
- Receptors, Cell Surface/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Stomach/cytology
- Transcription, Genetic
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Affiliation(s)
- I Cheng
- Department of Surgery, Brigham and Women's Hospital, and West Roxbury Veterans Administration Medical Center, Harvard Medical School, Boston, Massachusetts, USA
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17
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Bleecker AB, Esch JJ, Hall AE, Rodríguez FI, Binder BM. The ethylene-receptor family from Arabidopsis: structure and function. Philos Trans R Soc Lond B Biol Sci 1998; 353:1405-12. [PMID: 9800203 PMCID: PMC1692356 DOI: 10.1098/rstb.1998.0295] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.2] [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: 11/12/2022] Open
Abstract
The gaseous hormone ethylene regulates many aspects of plant growth and development. Ethylene is perceived by a family of high-affinity receptors typified by the ETR1 protein from Arabidopsis. The ETR1 gene codes for a protein which contains a hydrophobic N-terminal domain that binds ethylene and a C-terminal domain that is related in sequence to histidine kinase-response regulator two-component signal transducers found in bacteria. A structural model for the ethylene-binding domain is presented in which a Cu(I) ion is coordinated within membrane-spanning alpha-helices of the hydrophobic domain. It is proposed that binding of ethylene to the transition metal would induce a conformational change in the sensor domain that would be propagated to the cytoplasmic transmitter domain of the protein. A total of four additional genes that are related in sequence to ETR1 have been identified in Arabidopsis. Specific missense mutations in any one of the five genes leads to ethylene insensitivity in planta. Models for signal transduction that can account for the genetic dominance of these mutations are discussed.
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Affiliation(s)
- A B Bleecker
- Department of Botany, University of Wisconsin-Madison 53706, USA
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18
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Abstract
Electroneutral cation-chloride cotransporters are widely expressed and perform a variety of physiological roles. A novel gene family of five members, encompassing a Na+-Cl- transporter, two Na+-K+-2Cl- transporters and two K+-Cl- cotransporters, encodes these membrane proteins; homologous genes have also been identified in a prokaryote and a number of lower eukaryotes. The cotransporter proteins share a common predicted membrane topology, with twelve putative transmembrane segments flanked by long hydrophilic N- and C-terminal cytoplasmic domains. The molecular identification of these transporters has had a significant impact on the study of their function, regulation and pathophysiology.
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Affiliation(s)
- D B Mount
- Department of Medicine, Vanderbilt University, Nashville, TN 37232, USA
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19
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Riccardi D, Hall AE, Chattopadhyay N, Xu JZ, Brown EM, Hebert SC. Localization of the extracellular Ca2+/polyvalent cation-sensing protein in rat kidney. Am J Physiol 1998; 274:F611-22. [PMID: 9530279 DOI: 10.1152/ajprenal.1998.274.3.f611] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We previously identified transcripts encoding a G protein-coupled, extracellular calcium/polyvalent cation-sensing receptor, RaKCaR, in rat kidney (D. Riccardi, J. Park, W.-S. Lee, G. Gamba, E. M. Brown, and S. C. Hebert. Proc. Natl. Acad. Sci. USA 92:131-135, 1994), which was proposed to provide the mechanism for modulating a variety of renal functions in response to changes in extracellular Ca2+ (E. M. Brown. In: Handbook of Physiology. Bethesda, MD: Am. Physiol. Soc., 1992, sect. 8, vol. 2, chapt. 39, p. 1841-1916; and S. C. Hebert. Kidney Int. 50: 2129-2139, 1996). Here, we examine the cellular and regional distribution of receptor protein by immunofluorescence microscopy using a polyclonal antibody raised against a 22 amino acid region of the NH2 terminus of the receptor. The most intense fluorescence was seen at the basolateral border of cortical thick ascending limb cells. Basolateral staining for the receptor was also detected in medullary thick ascending limbs, in macula densa cells identified by costaining with antibody to brain nitric oxide synthase, NOS-B1, and in distal convoluted tubule cells distinguished by costaining for the apical thiazide-sensitive Na(+)-Cl- cotransporter. Apical anti-RaKCaR staining was detected at the base of the brush border of proximal tubules with decreasing intensity from S1 to S3 segments. In cortical collecting ducts, anti-RaKCaR staining was detected in some, but not all, type A intercalated cells identified by costaining with anti-H(+)-ATPase and anti-AE1 Cl-/HCO3- exchanger antibodies. The present study demonstrates that RaKCaR protein is expressed in many different nephron segments and that the polarity of receptor expression varies with cell type along the nephron. These results suggest potential roles for the extracellular Ca2+/ polyvalent cation-sensing receptor in responding to both circulating and urinary concentrations of divalent minerals and potentially other polyvalent cations (e.g., aminoglycoside antibiotics) to modulate nephron function.
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Affiliation(s)
- D Riccardi
- Renal Division, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2372, USA
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20
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Xu JZ, Hall AE, Peterson LN, Bienkowski MJ, Eessalu TE, Hebert SC. Localization of the ROMK protein on apical membranes of rat kidney nephron segments. Am J Physiol 1997; 273:F739-48. [PMID: 9374837 DOI: 10.1152/ajprenal.1997.273.5.f739] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The ATP-sensitive, inwardly rectifying K+ channel, ROMK, has been suggested to be the low-conductance ATP-sensitive K+ channel identified in apical membranes of mammalian renal thick ascending limb (TAL) and cortical collecting duct (CCD). Mutations in the human ROMK gene (KIR 1.2) have been identified in kindreds with neonatal Bartter's syndrome. In the present study, we generated polyclonal antibodies raised against both a COOH-terminal (amino acids 252-391) ROMK-maltose binding protein (MBP) fusion protein and an NH2-terminal (amino acids 34-49) ROMK peptide. Affinity-purified anti-ROMK COOH-terminal antibody detected the 45-kDa ROMK protein in kidney tissues and HEK-293 cells transfected with ROMK1 cDNA. The antibody also recognized 85- to 90-kDa proteins in kidney tissue; these higher molecular weight proteins were abolished by immunoabsorption with ROMK-MBP fusion protein and were also detected on Western blots using anti-ROMK NH2-terminal antibody. Immunofluoresence studies using anti-ROMK COOH-terminal antibody showed intense apical staining along the loop of Henle and distal nephron; staining with preimmune and immunoabsorbed serum was negative. When colocalized with distal nephron markers [the thiazide-sensitive cotransporter (rTSC1), the bumetanide-sensitive cotransporter (rBSC1), the vacuolar type H(+)-ATPase, and neuronal nitric oxide synthase (NOS I)], the ROMK protein was found primarily at the apical border of cells in the TAL, macula densa, distal convoluted tubule, and connecting tubule. Within the CCD, the ROMK protein was expressed in principal cells and was absent from intercalated cells. The tubule localization and polarity of ROMK staining are consistent with the distribution of ROMK mRNA and provide more support for ROMK being the low-conductance K+ secretory channel in the rat distal nephron.
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Affiliation(s)
- J Z Xu
- Division of Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
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Abstract
Nine hundred eighty undergraduates from a major university completed a questionnaire designed to collect data on the associations between parental drinking and the students' coping resources and well-being. Three groups were identified: those with a parental alcohol problem (DP+), those with no problem (DP-), and those who were unsure. Discriminant analysis revealed similarities between the DP+ and unsure participants on the response variables. The coping resource scores of the DP- group were significantly higher than the scores of the DP+ and unsure groups. The unsure group had the lowest mean scores on the total coping resources inventory and on the Cognitive, Emotional, and Spiritual and Philosophical subscales. The DP+ group had significantly lower scores than the DP- group on the Cognitive, Spiritual and Philosophical, and Physical scales. Although DP+ students' perception of well-being was significantly lower than that of their DP- peers, the entire sample was reasonably healthy, as measured by the General Well-Being Schedule.
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Affiliation(s)
- A E Hall
- College of Health and Human Development, Pennsylvania State University in New Kensington, USA
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22
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Abstract
We have sequenced a (CCA)n microsatellite-containing region of the y1 gene from 11 different lines of maize and 6 teosinte species, subspecies, or varieties. The (CCA)n microsatellite was found to vary in repeat number from 3 to 11. In addition, a pentanucleotide repeat adjacent to the trinucleotide microsatellite exhibits sequence and repeat number variation. Therefore, the (CCA)n microsatellite, as well as the sequence directly adjacent to it, exhibit variability in both maize and teosinte and could potentially serve as molecular markers in mapping or breeding studies.
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Affiliation(s)
- T L Phelps
- Division of Science, Northeast Missouri State University, Kirksville 63501, USA
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23
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Lilly CM, Hall AE, Rodger IW, Kobzik L, Haley KJ, Drazen JM. Substance P-induced histamine release in tracheally perfused guinea pig lungs. J Appl Physiol (1985) 1995; 78:1234-41. [PMID: 7542231 DOI: 10.1152/jappl.1995.78.4.1234] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [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: 01/25/2023] Open
Abstract
The capacity of substance P (SP) and endogenously released tachykinins to liberate histamine was examined in isolated tracheally perfused guinea pig lungs. Increasing doses of tracheally injected SP were associated with the recovery of increasing amounts of histamine from lung effluent. The mechanism of SP-induced histamine liberation was explored in studies with neurokinin-(NK) receptor agonists and antagonists. Tracheal injection of either the NK1 agonist [Sar9,Met(O2)11]SP or the NK2 agonist [beta-Ala8]-neurokinin A-(4-10) was associated with a significant increase in histamine recovery from lung effluent. In addition, both the NK1 antagonist CP-99994 and the NK2 antagonist SR-48968 significantly inhibited SP-induced histamine release. These findings support the hypothesis that SP can liberate histamine from guinea pigs lungs by a mechanism that depends predominantly on NK1- and NK2-receptor activation. The liberation of endogenous tachykinins by acute tracheal injection of capsaicin was also associated with augmented histamine recovery, which was inhibited by combined NK1- and NK2-receptor blockade. Tracheal injection of SP was associated with an increase in the percentage of airway mast cells exhibiting histological evidence of degranulation. This study demonstrates that exogenous SP, as well as endogenous tachykinins released from capsaicin-sensitive neurons, can liberate histamine, most likely from airway mast cells, by a mechanism that depends predominantly on the activation of NK1 and NK2 receptors.
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Affiliation(s)
- C M Lilly
- Department of Medicine, Beth Israel Hospital, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
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24
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Abstract
Tracheal and lung parenchymal SP-LI (substance P-like immunoreactivity) and VIP-LI (vasoactive intestinal peptide-like immunoreactivity) content was measured in HPLC-purified tissue extracts from patients with and without asthma. We detected significantly less SP-LI in tracheal tissue from asthmatic than from nonasthmatic patients, whereas parenchymal SP-LI content was not significantly different between these groups. This finding does not support the concept that asthmatic lungs contain excessive amounts of SP. Indeed, lower SP-LI content of tracheal tissues from asthmatic patients may reflect augmented SP release followed by degradation. We detected greater quantities of VIP-LI in tracheal than in parenchymal tissue in both groups, but did not detect significant differences in VIP-LI content in tracheal or parenchymal tissues from asthmatic and nonasthmatic patients. These findings indicate that asthmatic and nonasthmatic lungs contain similar levels of VIP.
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Affiliation(s)
- C M Lilly
- Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115
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25
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Lilly CM, Kobzik L, Hall AE, Drazen JM. Effects of chronic airway inflammation on the activity and enzymatic inactivation of neuropeptides in guinea pig lungs. J Clin Invest 1994; 93:2667-74. [PMID: 7515394 PMCID: PMC294512 DOI: 10.1172/jci117280] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The effects of airway inflammation induced by chronic antigen exposure on substance P (SP)-induced increases and vasoactive intestinal peptide (VIP)-induced decreases in airway opening pressure (Pao), and the recovery of intact and hydrolyzed radiopeptide were studied in tracheally perfused guinea pig lungs. SP (10(-6) mol/kg) induced a significantly greater increase in Pao in lungs from antigen-exposed (30 +/- 5 cm H2O) than saline-exposed animals (15 +/- 1 cm H2O, P < 0.05). Significantly more intact 3H-SP and significantly less 3H-SP 1-7, a neutral endopeptidase (NEP) hydrolysis product, were recovered from the lung effluent of antigen-exposed than saline-exposed animals (P < 0.05). Injection of VIP (10(-9) mol/kg) induced significantly more pulmonary relaxation in saline-exposed compared with antigen-exposed lungs (62 +/- 4%, P < 0.001). In contrast to effluent from saline-exposed animals, lung effluent from antigen-exposed lungs contained less intact VIP, increased amounts of a tryptic hydrolysis product, and no products consistent with the degradation of VIP by NEP. These data indicate that inflamed lungs are more sensitive to the contractile effects of SP because it is less efficiently degraded by NEP and are less sensitive to the relaxant effects of VIP because it is more efficiently degraded by a tryptic enzyme. Changes in airway protease activity occur with allergic inflammation and may contribute to airway hyperresponsiveness.
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Affiliation(s)
- C M Lilly
- Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115
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26
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Lewis AD, Hickson ID, Robson CN, Harris AL, Hayes JD, Griffiths SA, Manson MM, Hall AE, Moss JE, Wolf CR. Amplification and increased expression of alpha class glutathione S-transferase-encoding genes associated with resistance to nitrogen mustards. Proc Natl Acad Sci U S A 1988; 85:8511-5. [PMID: 3186741 PMCID: PMC282488 DOI: 10.1073/pnas.85.22.8511] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Glutathione-dependent enzymes play a central role in the protection of cells from cytotoxic chemicals and have been implicated in the intrinsic and acquired resistance of tumors to cytotoxic drugs. We have generated a Chinese hamster ovary line resistant to bifunctional nitrogen mustards and in this report have characterized and isolated the protein that represents the major observable phenotypic difference between the drug-sensitive and drug-resistant cell lines. This purified protein is shown to be an alpha class glutathione S-transferase comprising YcYc subunits and possessing a pI value of approximately 8.0. The intracellular level of the Yc subunit is elevated greater than 40-fold in the drug-resistant cell line, which could account for the increase in glutathione S-transferase (RX:glutathione R-transferase; EC 2.5.1.18) activity toward both 1-chloro-2,4-dinitrobenzene and cumene hydroperoxide. Other glutathione S-transferase subunits within this gene family are also elevated. These changes are accompanied by a significant elevation in alpha class mRNA levels. Southern analysis indicates that the genes coding for these proteins are amplified 4- to 8-fold in the drug-resistant cell line. In addition, gamma-glutamyl transpeptidase [(5-glutamyl)-peptide:amino acid 5-glutamyltransferase; EC 2.3.2.2] activity is increased 3.6-fold in the drug-resistant Chinese hamster ovary cell line, which may explain the increase in cellular glutathione level. In this case no gene amplification was seen. These data indicate that gene amplification may be important in drug resistance toward alkylating agents and also that other enzymes in glutathione homeostasis are involved.
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Affiliation(s)
- A D Lewis
- Imperial Cancer Research Fund, University Department of Biochemistry, Edinburgh, Scotland, United Kingdom
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27
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Hill RE, Hall AE, Sime CM, Hastie ND. A mouse homeo box-containing gene maps near a developmental mutation. Cytogenet Cell Genet 1987; 44:171-4. [PMID: 2882954 DOI: 10.1159/000132366] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Mouse genes containing homeo box domains are predicted to fulfill important functions in embryogenesis. Using recombinant inbred mouse strains, we have mapped a mouse gene which contains a homeo box with homology to the Drosophila engrailed gene. This gene maps to mouse chromosome 1 near or at the dominant hemimelia locus which is a known mouse developmental mutation.
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Bates LM, Hall AE. Relationships between leaf water status and transpiration of cowpea with progressive soil drying. Oecologia 1982; 53:285-289. [PMID: 28311727 DOI: 10.1007/bf00389000] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/1981] [Indexed: 11/28/2022]
Abstract
It was previously reported that leaf water status of cowpea (Vigna unguiculata) exhibited only small changes with progressive soil drying over extended periods of time. In these studies, under field conditions, it was demonstrated that when soil water was not limiting, xylem pressure potential (ψ x ) exhibited a linear relationship with transpirational flux density with no obvious hysteresis. With progressive soil drying, values of ψ x and transpiration rate fell below the regression line established for nonlimiting soil conditions. It is proposed that paired measurements of ψ x and transpirational flux density made between midday and sunset can provide a measure of the extent to which soil conditions are limiting water uptake. The relation between ψ x and transpiration exhibits a family of curves, with more negative slopes and decreases in maximum transpiration rate indicating progressive limitation due to soil drying.
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Affiliation(s)
- L M Bates
- Department of Botany and Plant Sciences, University of California, 92521, Riverside, CA, USA
| | - A E Hall
- Department of Botany and Plant Sciences, University of California, 92521, Riverside, CA, USA
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Grantz DA, Hall AE. Earliness of an indeterminate crop, Vigna unguiculata (L.) Walp., as affected by drought, temperature, and plant density. ACTA ACUST UNITED AC 1982. [DOI: 10.1071/ar9820531] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Earliness of an indeterminate crop, Vigna unguiculata (L.) Walp., was studied to aid development of selection techniques for improving adaptation to semiarid environments. Earliness was based upon the time of first appearance of floral buds and flowers, proportion of shoot dry matter in reproductive parts at midseason, and time of maturity. A cowpea land race, Chino 3, was earlier than cultivars California Blackeye No. 3 and No. 5, with respect to all of these criteria. Time to flowering from different sowing dates was related to heat units, which were calculated from daily mean air temperature above a base temperature of c. 10�C. The proportions of shoot dry matter in reproductive parts during early stages of pod-filling were greater with moderate drought but were unaffected by severe drought, compared with the response of adequately irrigated plants. Widely spaced plants exhibited greater proportions of shoot dry matter in reproductive parts at midseason than did closely spaced plants. Adaptation of cowpeas to semiarid environments may be improved by selecting for early partitioning of carbohydrates to reproductive parts. Selection for early partitioning may be more effective in adequately watered conditions, owing to extreme variability under drought, and at wide and precise spacing.
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Bates LM, Hall AE. Stomatal closure with soil water depletion not associated with changes in Bulk leaf water status. Oecologia 1981; 50:62-65. [PMID: 28310062 DOI: 10.1007/bf00378794] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/1981] [Indexed: 11/28/2022]
Abstract
It has previously been reported that canopy water loss by cowpea (Vigna unguiculata) decreases with small depletions in soil water. In these studies, under field conditions, it was demonstrated that with small changes in soil water status leaf conductance of cowpea decreases in a manner which is consistent with the sensitive regulation of canopy water loss.However, treatments which differed in leaf conductance, and presumably stomatal aperture, had similar leaf water potentials. It is hypothesized that the stomatal closure which results from soil water depletion is mediated by changes in root water status through effects on the flow of information from root to shoot. An efficient mechanism of this type could be partially responsible for the extreme drought avoidance exhibited by this plant.
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Affiliation(s)
- L M Bates
- Department of Botany and Plant Sciences, University of California, 92521, Riverside, CA, USA
| | - A E Hall
- Department of Botany and Plant Sciences, University of California, 92521, Riverside, CA, USA
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Abstract
Leaf resistance of Sesamum indicum L. increased when the humidity gradient between leaf and air was increased, at moderate temperatures, even though calculated carbon dioxide concentrations within the leaf decreased slightly. Mesophyll resistance remained relatively constant when humidity gradients were changed, indicating that the increases in leaf resistance were mainly caused by reductions in stomatal aperture and that nonstomatal aspects of photosynthesis and respiration were not affected. Low carbon dioxide concentrations inside the leaf decreased but did not eliminate resistance response to the humidity gradient. Internal carbon dioxide concentrations had little effect on resistance in humid air but had moderate effects on resistance with large humidity gradients between leaf and air. Stomatal response to humidity was not present at high leaf temperatures. Effects of humidity gradients on photosynthetic and stomatal responses to temperature suggested that large humidity gradients may contribute to mid-day closure of stomata and depressions in photosynthesis.
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Affiliation(s)
- A E Hall
- Department of Plant Science, University of California, Riverside, California 92502
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Camacho-B SE, Hall AE, Kaufmann MR. Efficiency and regulation of water transport in some woody and herbaceous species. Plant Physiol 1974; 54:169-72. [PMID: 16658853 PMCID: PMC541524 DOI: 10.1104/pp.54.2.169] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The efficiency with which plants transport water is related to the water potential differences required to drive water fluxes from the soil to the leaf. A comparative study of two woody and three herbaceous species (Citrus sinensis L. cv. Koethen, Pyrus kawakami L., Helianthus annuus L. cv. Mammoth Russian, Capsicum frutescens L. cv. Yolo Wonder, and Sesamum indicum L. cv. Glauca) indicated contrasts in water transport efficiency. Depression of leaf water potential in response to transpiration increases was found in the woody species; the herbaceous species, however, had more efficient water transport systems and presented no measurable response of leaf water potential to transpiration changes. Different maximum transpiration rates under the same climatic conditions were observed with different species and may be accounted for by stomatal response to humidity gradients between leaf and air. Leaf diffusion resistance in sesame increased markedly as the humidity gradient was increased, while leaf resistance of sunflower responded less to humidity. Stomata appeared to respond directly to the humidity gradient because changes in leaf water potential were not detected when leaf resistance increased or decreased.
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Affiliation(s)
- S E Camacho-B
- Department of Plant Science, University of California, Riverside, California 92502
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Hall AE, Loomis RS. An Explanation for the Difference in Photosynthetic Capabilities of Healthy and Beet Yellows Virus-infected Sugar Beets (Beta vulgaris L.). Plant Physiol 1972; 50:576-80. [PMID: 16658220 PMCID: PMC366193 DOI: 10.1104/pp.50.5.576] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Sugar beets (Beta vulgaris L.) infected with the Beet Yellows Virus exhibit lower rates of net photosynthesis at light saturation than do healthy plants. These Pn reductions were correlated with increases in leaf resistance to water vapor loss. Theoretical analyses demonstrated that, although the leaf resistance to water vapor loss increases could account for a major part of the net photosynthesis decreases, some other aspect of leaf functioning also was debilitated by infection. Both the levels and the activities of ribulose-1, 5-diP carboxylase were less on a leaf area basis in extracts from infected leaves than from healthy ones. Soluble carbohydrates accumulate in Beet Yellows Virus-infected leaves, but inhibiting translocation in several ways provided no evidence in support of the hypothesis that the accumulation of photosynthates in leaves has a direct, short term, feed-back effect upon the photosynthetic rate.
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Affiliation(s)
- A E Hall
- Department of Agronomy and Range Science, University of California, Davis, California 95616
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34
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Hall AE, Hilton EL, West DC. Neuromuscular transmission in potassium-free Krebs solution. J Physiol 1972; 226:95P-96P. [PMID: 4343635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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Miller BJ, Russ D, Gibson C, Hall AE. Effects of free association training, retraining, and information on creativity. J Exp Psychol 1970; 84:226-9. [PMID: 5480921 DOI: 10.1037/h0029217] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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37
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