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Miller LJ, Saterbak A, Parsons LN, Singh R, Bone KM. Atypical Presentation in Sclerosing Epithelioid Fibrosarcoma: A Case Report. Am J Clin Pathol 2022. [DOI: 10.1093/ajcp/aqac126.072] [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: 11/11/2022] Open
Abstract
Abstract
Introduction/Objective
Sclerosing Epithelioid Fibrosarcoma (SEF) is a rare sarcoma with characteristic EWSR1::CREB3L1 fusion and MUC4 positivity by immunohistochemistry (IHC). SEF most often presents as a primary soft tissue tumor in the lower extremities. Histologically, SEF is characterized by cords, nests or sheets of monotonous, epithelioid tumor cells in a dense collagenous background. We report a case of SEF in an atypical location with unique histological and atypical cytogenetic findings.
Methods/Case Report
A 13-year-old male presented with left leg and back pain. A CT scan demonstrated a 7.3 x 5.7 x 6.8 cm left hemiabdomen mesenteric mass with metastatic nodules in the pancreas, liver, L1 vertebrae and sacrum. Sacral biopsy demonstrated infiltrative and discohesive nests of small to medium round cells with scant eosinophilic to clear cytoplasm but without conspicuous tumor stroma. An extensive IHC panel was positive only for CD99. Fluorescence in-situ hybridization (FISH) demonstrated an unusual finding with a variant pattern. FISH revealed an EWSR1 rearrangement with an unidentified partner. The tumor karyotype was normal in the dividing cells utilized for chromosome analysis, suggesting the rearrangement was enriched in the non-dividing cell population. Next- generation sequencing (NGS) revealed a EWSR1::CREB3L1 fusion that was confirmed by FISH, and MUC4 was positive by IHC, further supporting classification as SEF.
Results (if a Case Study enter NA)
NA
Conclusion
Due to the atypical presentation and histologic appearance of this rare sarcoma, integration of IHC, FISH, and NGS were required to fully characterize the lesion.
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Affiliation(s)
- L J Miller
- Pathology, University of Michigan , Ann Arbor, Michigan , United States
| | - A Saterbak
- Pathology, Medical College of Wisconsin , Milwaukee, Wisconsin , United States
| | - L N Parsons
- Pathology, Medical College of Wisconsin , Milwaukee, Wisconsin , United States
| | - R Singh
- Pathology, Medical College of Wisconsin , Milwaukee, Wisconsin , United States
| | - K M Bone
- Pathology, Medical College of Wisconsin , Milwaukee, Wisconsin , United States
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Hall K, Bryant J, Staley M, Whitham JC, Miller LJ. Behavioural diversity as a potential welfare indicator for professionally managed chimpanzees (Pan troglodytes): Exploring variations in calculating diversity using species-specific behaviours. Anim Welf 2021. [DOI: 10.7120/09627286.30.4.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Behavioural diversity may serve as a positive indicator of animal welfare that can be applied in long-term monitoring schemes in managed settings (eg zoos, laboratories, farms). Behavioural diversity is often higher when animals live in stimulating environments and experience positive
events. Unfortunately, welfare researchers have not adopted consistent, standardised approaches to measuring behavioural diversity. The goal of this exploratory study was to utilise data from 41 adult chimpanzees (Pan troglodytes) housed across 16 zoological institutions to examine
various models of Shannon's Diversity Index. Specifically, we investigated the impact of: combining versus splitting behaviours, including only positive behaviours, including human interaction, and considering recipient behaviours. We evaluate how the inclusion or exclusion of different behaviours
impacts the relationship of behavioural diversity with: (i) concentrations of faecal glucocorticoid metabolites (GCM), a common indicator of adrenal activity; (ii) concentrations of immunoglobulin-A (IgA), an indicator of immune function and potential indicator of positive welfare; and (iii)
stereotypic behaviour, a validated indicator of poor welfare. Most indices had significant negative relationships with faecal GCM. Animals that express a variety of behaviours from their species-typical repertoire have lower average faecal GCM concentrations and are likely experiencing better
welfare. We did not find significant relationships between the behavioural diversity indices and IgA concentrations. Two indices were inversely associated with stereotypic behaviour. Our findings provide additional support for using Shannon's Diversity Index to calculate behavioural diversity
as a robust, valid measure of positive welfare. However, future publications must justify the process for including or excluding behaviours from calculations.
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Lauderdale LK, Miller LJ. Efficacy of an interactive apparatus as environmental enrichment for common bottlenose dolphins (Tursiops truncatus). Anim Welf 2020. [DOI: 10.7120/09627286.29.4.379] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Environmental enrichment is a key component in improving the psychological and physiological well-being of animals under professional care. Environmental enrichment involves the addition of stimuli, including objects and cognitive challenges, into the environment in order to increase
species-specific behaviour and provide opportunities for choice and control. The effectiveness of enrichment should be evaluated on a case-by-case basis to determine if the desired result has been achieved. Environmental enrichment devices (EEDs) can be utilised to present novel problems to
animals under professional care. Here, a submerged interactive cognitive apparatus was presented to eight bottlenose dolphins (Tursiops truncatus) five days a week for 18 weeks and behavioural indicators of animal welfare assessed. As a group, dolphins spent more time in social swims
compared to solitary swims and more time at the bottom of the habitat than the middle or top throughout the day, even when the apparatus was not immediately available. Individuals' differences were apparent in the type and amount of engagement with the apparatus. Three dolphins engaged with
the apparatus by solving it or consuming the reward. Two dolphins, D4 and D8, engaged simultaneously with the apparatus and participated in more social swimming with each other. D4 solved the interactive apparatus and engaged in more social active and solitary active behaviours. D1 and D4
increased their use of the bottom of the habitat. This study is the first report of underwater enrichment increasing dolphins time at depth throughout the day even when the enrichment device is not available. The interactive apparatus was an effective form of enrichment for dolphins participating
in successful trials.
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Lauderdale LK, Miller LJ. Common bottlenose dolphin (Tursiops truncatus) problem solving strategies in response to a novel interactive apparatus. Behav Processes 2019; 169:103990. [PMID: 31678324 DOI: 10.1016/j.beproc.2019.103990] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 08/06/2019] [Revised: 10/21/2019] [Accepted: 10/22/2019] [Indexed: 11/29/2022]
Abstract
The problem solving capabilities of dolphins are suggested to be indicative of advanced cognition. When confronted with a novel problem, dolphins can plan their behavior to create a more efficient strategy than that which was previously modeled. The present study investigated dolphins' ability to plan their behaviors using an interactive apparatus with accompanying weights. Two problems were presented to evaluate dolphins' ability to plan by collecting several weights at once, thus solving the apparatus more efficiently. In contrast to previous findings, dolphins in the present study failed to plan their behavior. Rather, individual differences in problem solving strategies arose throughout the study and are described here. Dolphins engaged in several strategies in order to attempt to obtain the fish reward, including approaches that were not modeled. Strategies for solving the submerged interactive apparatus (SIA) included emulation, freeloading, water flow manipulation, and physical manipulation of the SIA. The SIA was continually solved by a single individual who rarely consumed the food reward, suggesting that she may have been motivated to participate for the challenge itself. Though not indicative of planning, the results of the present study demonstrate the plasticity of dolphin problem solving capabilities and spatial reasoning.
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Affiliation(s)
- L K Lauderdale
- Department of Psychology, University of Southern Mississippi, 118 College Drive, Hattiesburg, MS 39406, USA; Chicago Zoological Society, Brookfield Zoo, 3300 Golf Road, Brookfield, IL 60513, USA
| | - L J Miller
- Chicago Zoological Society, Brookfield Zoo, 3300 Golf Road, Brookfield, IL 60513, USA
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Hacker CE, Miller LJ, Schulte BA. Examination of enrichment using space and food for African elephants (Loxodonta africana) at the San Diego Zoo Safari Park. Anim Welf 2018. [DOI: 10.7120/09627286.27.1.055] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Erfanian M, Jo Brout J, Edelstein M, Kumar S, Mannino M, Miller LJ, Rouw R, Rosenthal MZ. REMOVED: Investigating misophonia: A review of the literature, clinical implications and research agenda reflecting current neuroscience and emotion research perspectives. Eur Psychiatry 2017; 41S:S681. [PMID: 28859824 DOI: 10.1016/j.eurpsy.2017.01.1180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 10/19/2022] Open
Abstract
This article has been removed: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been removed at the request of the authors due to errors in the author list.
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Affiliation(s)
- M Erfanian
- Maastricht University, Neuroscience and Psychology, Maastricht, The Netherlands
| | - J Jo Brout
- International Misophonia Research Network, Misophonia, New York, USA
| | - M Edelstein
- University of California, Brain and Cognition, San Diego, USA
| | - S Kumar
- Newcastle University, Neuroscience, Newcastle, United Kingdom
| | - M Mannino
- Florida Atlantic University, Complex Systems and Brain Sciences, Boca Raton, USA
| | - L J Miller
- STAR Institute for Sensory Processing Disorder, Sensory Processing Disorder, Greenwood Village, USA
| | - R Rouw
- Amsterdam University, Brain and Cognition, Amsterdam, The Netherlands
| | - M Z Rosenthal
- Duke University, Psychiatry and Behavioral Science, Durham, USA
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Desai AJ, Dong M, Harikumar KG, Miller LJ. Cholecystokinin-induced satiety, a key gut servomechanism that is affected by the membrane microenvironment of this receptor. Int J Obes Suppl 2016; 6:S22-S27. [PMID: 28685026 DOI: 10.1038/ijosup.2016.5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The gastrointestinal (GI) tract has a central role in nutritional homeostasis, as location for food ingestion, digestion and absorption, with the gut endocrine system responding to and regulating these events, as well as influencing appetite. One key GI hormone with the full spectrum of these activities is cholecystokinin (CCK), a peptide released from neuroendocrine I cells scattered through the proximal intestine in response to fat and protein, with effects to stimulate gall bladder contraction and pancreatic exocrine secretion, to regulate gastric emptying and intestinal transit, and to induce satiety. There has been interest in targeting the type 1 CCK receptor (CCK1R) for drug development to provide non-caloric satiation as an aid to dieting and weight loss; however, there have been concerns about CCK1R agonists related to side effects and potential trophic impact on the pancreas. A positive allosteric modulator (PAM) of CCK action at this receptor without intrinsic agonist activity could provide a safer and more effective approach to long-term administration. In addition, CCK1R stimulus-activity coupling has been shown to be negatively affected by excess membrane cholesterol, a condition described in the metabolic syndrome, thereby potentially interfering with an important servomechanism regulating appetite. A PAM targeting this receptor could also potentially correct the negative impact of cholesterol on CCK1R function. We will review the molecular basis for binding natural peptide agonist, binding and action of small molecules within the allosteric pocket, and the impact of cholesterol. Novel strategies for taking advantage of this receptor for the prevention and management of obesity will be reviewed.
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Affiliation(s)
- A J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - M Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - K G Harikumar
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - L J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
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Miller LJ, Pisacane CB, Vicino GA. Relationship between behavioural diversity and faecal glucocorticoid metabolites: a case study with cheetahs (Acinonyx jubatus). Anim Welf 2016. [DOI: 10.7120/09627286.25.3.325] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Dong M, Koole C, Wootten D, Sexton PM, Miller LJ. Structural and functional insights into the juxtamembranous amino-terminal tail and extracellular loop regions of class B GPCRs. Br J Pharmacol 2014; 171:1085-101. [PMID: 23889342 DOI: 10.1111/bph.12293] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [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: 04/11/2013] [Revised: 06/22/2013] [Accepted: 06/29/2013] [Indexed: 12/24/2022] Open
Abstract
Class B guanine nucleotide-binding protein GPCRs share heptahelical topology and signalling via coupling with heterotrimeric G proteins typical of the entire superfamily of GPCRs. However, they also exhibit substantial structural differences from the more extensively studied class A GPCRs. Even their helical bundle region, most conserved across the superfamily, is predicted to differ from that of class A GPCRs. Much is now known about the conserved structure of the amino-terminal domain of class B GPCRs, coming from isolated NMR and crystal structures, but the orientation of that domain relative to the helical bundle is unknown, and even less is understood about the conformations of the juxtamembranous amino-terminal tail or of the extracellular loops linking the transmembrane segments. We now review what is known about the structure and function of these regions of class B GPCRs. This comes from indirect analysis of structure-function relationships elucidated by mutagenesis and/or ligand modification and from the more direct analysis of spatial approximation coming from photoaffinity labelling and cysteine trapping studies. Also reviewed are the limited studies of structure of some of these regions. No dominant theme was recognized for the structures or functional roles of distinct regions of these juxtamembranous portions of the class B GPCRs. Therefore, it is likely that a variety of molecular strategies can be engaged for docking of agonist ligands and for initiation of conformational changes in these receptors that would be expected to converge to a common molecular mechanism for activation of intracellular signalling cascades.
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Affiliation(s)
- M Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
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Alexander SPH, Benson HE, Faccenda E, Pawson AJ, Sharman JL, McGrath JC, Catterall WA, Spedding M, Peters JA, Harmar AJ, Abul-Hasn N, Anderson CM, Anderson CMH, Araiksinen MS, Arita M, Arthofer E, Barker EL, Barratt C, Barnes NM, Bathgate R, Beart PM, Belelli D, Bennett AJ, Birdsall NJM, Boison D, Bonner TI, Brailsford L, Bröer S, Brown P, Calo G, Carter WG, Catterall WA, Chan SLF, Chao MV, Chiang N, Christopoulos A, Chun JJ, Cidlowski J, Clapham DE, Cockcroft S, Connor MA, Cox HM, Cuthbert A, Dautzenberg FM, Davenport AP, Dawson PA, Dent G, Dijksterhuis JP, Dollery CT, Dolphin AC, Donowitz M, Dubocovich ML, Eiden L, Eidne K, Evans BA, Fabbro D, Fahlke C, Farndale R, Fitzgerald GA, Fong TM, Fowler CJ, Fry JR, Funk CD, Futerman AH, Ganapathy V, Gaisnier B, Gershengorn MA, Goldin A, Goldman ID, Gundlach AL, Hagenbuch B, Hales TG, Hammond JR, Hamon M, Hancox JC, Hauger RL, Hay DL, Hobbs AJ, Hollenberg MD, Holliday ND, Hoyer D, Hynes NA, Inui KI, Ishii S, Jacobson KA, Jarvis GE, Jarvis MF, Jensen R, Jones CE, Jones RL, Kaibuchi K, Kanai Y, Kennedy C, Kerr ID, Khan AA, Klienz MJ, Kukkonen JP, Lapoint JY, Leurs R, Lingueglia E, Lippiat J, Lolait SJ, Lummis SCR, Lynch JW, MacEwan D, Maguire JJ, Marshall IL, May JM, McArdle CA, McGrath JC, Michel MC, Millar NS, Miller LJ, Mitolo V, Monk PN, Moore PK, Moorhouse AJ, Mouillac B, Murphy PM, Neubig RR, Neumaier J, Niesler B, Obaidat A, Offermanns S, Ohlstein E, Panaro MA, Parsons S, Pwrtwee RG, Petersen J, Pin JP, Poyner DR, Prigent S, Prossnitz ER, Pyne NJ, Pyne S, Quigley JG, Ramachandran R, Richelson EL, Roberts RE, Roskoski R, Ross RA, Roth M, Rudnick G, Ryan RM, Said SI, Schild L, Sanger GJ, Scholich K, Schousboe A, Schulte G, Schulz S, Serhan CN, Sexton PM, Sibley DR, Siegel JM, Singh G, Sitsapesan R, Smart TG, Smith DM, Soga T, Stahl A, Stewart G, Stoddart LA, Summers RJ, Thorens B, Thwaites DT, Toll L, Traynor JR, Usdin TB, Vandenberg RJ, Villalon C, Vore M, Waldman SA, Ward DT, Willars GB, Wonnacott SJ, Wright E, Ye RD, Yonezawa A, Zimmermann M. The Concise Guide to PHARMACOLOGY 2013/14: overview. Br J Pharmacol 2014; 170:1449-58. [PMID: 24528237 DOI: 10.1111/bph.12444] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The Concise Guide to PHARMACOLOGY 2013/14 provides concise overviews of the key properties of over 2000 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties from the IUPHAR database. The full contents can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.12444/full. This compilation of the major pharmacological targets is divided into seven areas of focus: G protein-coupled receptors, ligand-gated ion channels, ion channels, catalytic receptors, nuclear hormone receptors, transporters and enzymes. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. A new landscape format has easy to use tables comparing related targets. It is a condensed version of material contemporary to late 2013, which is presented in greater detail and constantly updated on the website www.guidetopharmacology.org, superseding data presented in previous Guides to Receptors & Channels. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and GRAC and provides a permanent, citable, point-in-time record that will survive database updates.
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Affiliation(s)
- Stephen P H Alexander
- School of Life Sciences, University of Nottingham Medical School, Nottingham, NG7 2UH, UK
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Miller LJ, Sexton PM, Dong M, Harikumar KG. The class B G-protein-coupled GLP-1 receptor: an important target for the treatment of type-2 diabetes mellitus. Int J Obes Suppl 2014; 4:S9-S13. [PMID: 27152167 DOI: 10.1038/ijosup.2014.4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) is a gastrointestinal hormone secreted from L cells in the distal small intestine and proximal colon after a meal that acts as an incretin to augment the insulin response, while also inhibiting glucagon and slowing gastric emptying. These characteristics of GLP-1, as well as its ability to reduce islet beta cell apoptosis and expand beta cell mass and its cardioprotective and neuroprotective effects, provide a broad spectrum of actions potentially useful for the management of type-2 diabetes mellitus. GLP-1 also has the added advantage of having its incretin effects dependent on the level of serum glucose, only acting in the presence of hyperglycaemia, and thereby preventing hypoglycemic responses. Although natural GLP-1 has a very short half-life, limiting its therapeutic usefulness, a variety of analogues and formulations have been developed to provide extended actions and to limit side effects. However, all of these peptides require parenteral administration. Potentially orally active small-molecule agonists acting at the GLP-1 receptor are also being developed, but have not yet been approved for clinical use. Recent insights into the molecular nature of the class B G-protein-coupled GLP-1 receptor has provided insights into the modes of binding these types of ligands, as well as providing opportunities for rational enhancement. The advantages and disadvantages of each of these agents and their possible clinical utility will be explored.
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Affiliation(s)
- L J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic , Scottsdale, AZ, USA
| | - P M Sexton
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University , Parkville, Victoria, Australia
| | - M Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic , Scottsdale, AZ, USA
| | - K G Harikumar
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic , Scottsdale, AZ, USA
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Qi T, Dong M, Watkins HA, Wootten D, Miller LJ, Hay DL. Receptor activity-modifying protein-dependent impairment of calcitonin receptor splice variant Δ(1-47)hCT((a)) function. Br J Pharmacol 2013; 168:644-57. [PMID: 22946511 DOI: 10.1111/j.1476-5381.2012.02197.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 08/07/2012] [Accepted: 08/10/2012] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Alternative splicing expands proteome diversity to GPCRs. Distinct receptor variants have been identified for a secretin family GPCR, the calcitonin receptor (CTR). The possible functional contributions of these receptor variants are further altered by their potential interactions with receptor activity-modifying proteins (RAMPs). One variant of the human CTR lacks the first 47 residues at its N terminus [Δ(1-47)hCT((a)) ]. However, very little is known about the pharmacology of this variant or its ability to interact with RAMPs to form amylin receptors. EXPERIMENTAL APPROACH Δ(1-47)hCT((a)) was characterized both with and without RAMPs in Cos7 and/or HEK293S cells. The receptor expression (ELISA assays) and function (cAMP and pERK1/2 assays) for up to six agonists and two antagonists were determined. KEY RESULTS Despite lacking 47 residues at the N terminus, Δ(1-47)hCT((a)) was still able to express at the cell surface, but displayed a generalized reduction in peptide potency. Δ(1-47)hCT((a)) retained its ability to interact with RAMP1 and formed a functional amylin receptor; this also appeared to be the case with RAMP3. On the other hand, its interaction with RAMP2 and resultant amylin receptor was reduced to a greater extent. CONCLUSIONS AND IMPLICATIONS Δ(1-47)hCT((a)) acts as a functional receptor at the cell surface. It exhibits altered receptor function, depending on whether it associates with a RAMP and which RAMP it interacts with. Therefore, the presence of this variant in tissues will potentially contribute to altered peptide binding and signalling, depending on the RAMP distribution in tissues.
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Affiliation(s)
- T Qi
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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Miller LJ, Zeigler-Hill V, Mellen J, Koeppel J, Greer T, Kuczaj S. Dolphin shows and interaction programs: benefits for conservation education? Zoo Biol 2012; 32:45-53. [PMID: 22622768 DOI: 10.1002/zoo.21016] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 02/03/2012] [Accepted: 02/10/2012] [Indexed: 11/10/2022]
Abstract
Dolphin shows and dolphin interaction programs are two types of education programs within zoological institutions used to educate visitors about dolphins and the marine environment. The current study examined the short- and long-term effects of these programs on visitors' conservation-related knowledge, attitude, and behavior. Participants of both dolphin shows and interaction programs demonstrated a significant short-term increase in knowledge, attitudes, and behavioral intentions. Three months following the experience, participants of both dolphin shows and interaction programs retained the knowledge learned during their experience and reported engaging in more conservation-related behaviors. Additionally, the number of dolphin shows attended in the past was a significant predictor of recent conservation-related behavior suggesting that repetition of these types of experiences may be important in inspiring people to conservation action. These results suggest that both dolphin shows and dolphin interaction programs can be an important part of a conservation education program for visitors of zoological facilities.
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Affiliation(s)
- L J Miller
- Department of Psychology, The University of Southern Mississippi, Hattiesburg, Mississippi, USA.
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Harms MB, Ori-McKenney KM, Scoto M, Tuck EP, Bell S, Ma D, Masi S, Allred P, Al-Lozi M, Reilly MM, Miller LJ, Jani-Acsadi A, Pestronk A, Shy ME, Muntoni F, Vallee RB, Baloh RH. Mutations in the tail domain of DYNC1H1 cause dominant spinal muscular atrophy. Neurology 2012; 78:1714-20. [PMID: 22459677 DOI: 10.1212/wnl.0b013e3182556c05] [Citation(s) in RCA: 147] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To identify the gene responsible for 14q32-linked dominant spinal muscular atrophy with lower extremity predominance (SMA-LED, OMIM 158600). METHODS Target exon capture and next generation sequencing was used to analyze the 73 genes in the 14q32 linkage interval in 3 SMA-LED family members. Candidate gene sequencing in additional dominant SMA families used PCR and pooled target capture methods. Patient fibroblasts were biochemically analyzed. RESULTS Regional exome sequencing of all candidate genes in the 14q32 interval in the original SMA-LED family identified only one missense mutation that segregated with disease state-a mutation in the tail domain of DYNC1H1 (I584L). Sequencing of DYNC1H1 in 32 additional probands with lower extremity predominant SMA found 2 additional heterozygous tail domain mutations (K671E and Y970C), confirming that multiple different mutations in the same domain can cause a similar phenotype. Biochemical analysis of dynein purified from patient-derived fibroblasts demonstrated that the I584L mutation dominantly disrupted dynein complex stability and function. CONCLUSIONS We demonstrate that mutations in the tail domain of the heavy chain of cytoplasmic dynein (DYNC1H1) cause spinal muscular atrophy and provide experimental evidence that a human DYNC1H1 mutation disrupts dynein complex assembly and function. DYNC1H1 mutations were recently found in a family with Charcot-Marie-Tooth disease (type 2O) and in a child with mental retardation. Both of these phenotypes show partial overlap with the spinal muscular atrophy patients described here, indicating that dynein dysfunction is associated with a range of phenotypes in humans involving neuronal development and maintenance.
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Affiliation(s)
- M B Harms
- Department of Neurology, Hope Center for Neurological Disease,Washington University School of Medicine, St. Louis, MO, USA.
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Kuhar CW, Miller LJ, Lehnhardt J, Christman J, Mellen JD, Bettinger TL. A system for monitoring and improving animal visibility and its implications for zoological parks. Zoo Biol 2009; 29:68-79. [PMID: 19382165 DOI: 10.1002/zoo.20245] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
With the growing trend in zoos to build complex, naturalistic exhibits comes the potential for exhibits to be so densely vegetated or complex that animals are not easily seen by zoo visitors. This can negatively impact the visitor's visiting experience and the zoo's ability to communicate conservation and education messages. Over the past 9 years, Disney's Animal Kingdom has developed a process for monitoring and improving the visibility of animals on display to the public. This animal visibility process utilizes a data collection system whereby systematic observations are collected each week. The percentage of observations where at least one animal was visible is recorded for each species and compared to an 80% visibility criterion. Species that do not reach this criterion for 4 consecutive weeks are discussed at animal management meetings. If the problems associated with animal visibility cannot be easily solved, the animal-care teams partner with the research team to conduct a second process, called the Visibility Issues Process. This process provides additional information for the animal-care team to utilize in developing a plan to improve visibility. Although the processes described here are specific to the infrastructure at Disney's Animal Kingdom, the basic concepts of (1) a formalized visibility data collection process, (2) a visibility criterion to which managers of species are held accountable, and (3) a process for planning to improve animal visibility without negatively impacting animal welfare are fundamental concepts that can be developed at individual institutions and incorporated into that zoo's existing infrastructure.
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Affiliation(s)
- C W Kuhar
- Disney's Animal Kingdom, Lake Buena Vista, Florida 32830, USA
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Miller LJ, Dong M, Harikumar KG, Gao F. Structural basis of natural ligand binding and activation of the Class II G-protein-coupled secretin receptor. Biochem Soc Trans 2007; 35:709-12. [PMID: 17635130 DOI: 10.1042/bst0350709] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [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: 11/17/2022]
Abstract
The secretin receptor is prototypic of Class II GPCRs (G-protein-coupled receptors), based on its structural and functional characteristics and those of its natural agonist ligand. Secretin represents a linear 27-residue peptide with diffuse pharmacophoric domain. The secretin receptor includes the typical signature sequences for this receptor family within its predicted transmembrane segments and the highly conserved six cysteine residues contributing to three intradomain disulfide bonds within its long N-terminus. This domain is critical for secretin binding based on receptor mutagenesis and photoaffinity labelling studies. Full agonist analogues of secretin incorporating a photolabile moiety at various positions throughout the pharmacophore covalently label residues within this region, while only N-terminal probes have labelled the core helical bundle domain. Combining insights coming from receptor structural studies, peptide structure-activity relationship considerations, photoaffinity labelling, and application of fluorescence techniques has resulted in the development of a working model of the secretin-receptor complex. This supports the initial docking of the peptide agonist within a cleft in the receptor N-terminus, providing the opportunity for an endogenous sequence within that domain to interact with the core of the receptor. This interaction is believed to be key in the molecular basis of conformational change associated with activation of this receptor. The site of action of this endogenous agonist could also provide a possible target for small molecule agonists to act.
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Affiliation(s)
- L J Miller
- Mayo Clinic, 13400 East Shea Boulevard, Scottsdale, AZ 85259, USA.
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20
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Abstract
The receptor for the peptide hormone, cholecystokinin, is a G-protein-coupled receptor in the rhodopsin/beta-adrenergic receptor family. A number of methodological approaches have been utilized to gain insights into the molecular basis for natural peptide ligand binding and activation of this physiologically important receptor. Insights into this have come from sequence analysis, ligand and receptor structure-activity data, receptor mutagenesis, conformational analysis of ligand and receptor fragments, and photoaffinity labeling. In this work, we review the contributions of each of these complementary approaches and provide a current integrated view of the active complex of cholecystokinin bound to its receptor.
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Affiliation(s)
- L J Miller
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minn., USA.
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21
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Abstract
The purpose of this study was to examine the predictive validity of the Miller Assessment for Preschoolers in a sample of children in Israel. 30 children (M age 7 yr., 8 mo.) were selected from a group of typical children registered in 4 Mother and Child Health Care Centers in central Israel; they were originally tested as preschoolers (M age 3 yr., 10 mo.) on this procedure. They were retested after an interval of 5 to 7 yr. on academically related tests. Correlations between the Total scores and most of the follow-up test scores indicate significant correspondence (.41-.70). Regression analysis indicated that visuomotor integration and handwriting accounted for 58% of the variance. These results contribute to the empirical evidence regarding the predictive abilities of this procedure and indicate its validity cross-culturally over an extended follow-up interval of 5 to 7 yr.
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Affiliation(s)
- S Parush
- School of Occupational Therapy, Faculty of Medicine, The Hebrew University of Jerusalem, Mount Scopus, Israel
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22
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Miller LJ, Margerum JD, Rust JB, Brault RG, Lackner AM. Photopolymerization Studies. III. Thermal Sensitization and Desensitization Effects. Macromolecules 2002. [DOI: 10.1021/ma60038a006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zermeño M, Bianchi D, Miller LJ, Flaig KW, Iranpour R. RAPID BOD MEASUREMENT TECHNOLOGY TO PREVENT INDUSTRIAL WASTE IMPACT ON MUNICIPAL WASTEWATER PLANTS. ACTA ACUST UNITED AC 2002. [DOI: 10.2175/193864702784900057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Cheng ZJ, Miller LJ. Agonist-dependent dissociation of oligomeric complexes of G protein-coupled cholecystokinin receptors demonstrated in living cells using bioluminescence resonance energy transfer. J Biol Chem 2001; 276:48040-7. [PMID: 11673456 DOI: 10.1074/jbc.m105668200] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.5] [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: 11/06/2022] Open
Abstract
Dimerization of some G protein-coupled receptors has recently been demonstrated, but how widespread this phenomenon might be and its functional implications are not yet clear. We have utilized biophysical and biochemical techniques to evaluate whether the type A cholecystokinin (CCK) receptor can form oligomeric complexes in the plasma membrane and the impact of ligand binding and signaling on such complexes. We investigated the possibility of bioluminescence resonance energy transfer (BRET) between receptor constructs that included carboxyl-terminal tags of Renilla luciferase or yellow fluorescent protein. Indeed, co-expression of these constructs in COS cells resulted in the constitutive presence of a significant BRET signal above that in a series of controls, with this signal reduced by co-expression of competing non-tagged CCK receptors. The presence of an oligomeric complex of CCK receptor molecules was confirmed in co-immunoprecipitation experiments. Occupation of CCK receptors with agonist ligands (CCK or gastrin-4) resulted in the rapid reduction in BRET signal in contrast to the enhancement of such a signal reported after agonist occupation of the beta(2)-adrenergic receptor. These effects on CCK receptor oligomerization were concentration-dependent, correlating with the potencies of the agonists. A smaller effect was observed for a partial agonist, and no effect was observed for antagonist occupation of this receptor. Agonist-induced reduction in BRET signal was also observed for pairs of CCK receptors with a donor-acceptor pair situated in other positions within the receptor. Manipulation of the phosphorylation state of CCK receptor using protein kinase C activation with phorbol ester or inhibition with staurosporine had no effect on the basal level or agonist effect on CCK receptor oligomerization. This provides the first evidence for CCK receptor oligomerization in living cells, with insights that the active conformation of this receptor dissociates these complexes in a phosphorylation-independent manner.
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Affiliation(s)
- Z J Cheng
- Center for Basic Research in Digestive Diseases, Department of Medicine, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Shin DM, Luo X, Wilkie TM, Miller LJ, Peck AB, Humphreys-Beher MG, Muallem S. Polarized expression of G protein-coupled receptors and an all-or-none discharge of Ca2+ pools at initiation sites of [Ca2+]i waves in polarized exocrine cells. J Biol Chem 2001; 276:44146-56. [PMID: 11553617 DOI: 10.1074/jbc.m105203200] [Citation(s) in RCA: 51] [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
In the present work we examined localization and behavior of G protein-coupled receptors (GPCR) in polarized exocrine cells to address the questions of how luminal to basal Ca(2+) waves can be generated in a receptor-specific manner and whether quantal Ca(2+) release reflects partial release from a continuous pool or an all-or-none release from a compartmentalized pool. Immunolocalization revealed that expression of GPCRs in polarized cells is not uniform, with high levels of GPCR expression at or near the tight junctions. Measurement of phospholipase Cbeta activity and receptor-dependent recruitment and trapping of the box domain of RGS4 in GPCRs complexes indicated autonomous functioning of G(q)-coupled receptors in acinar cells. These findings explain the generation of receptor-specific Ca(2+) waves and why the waves are always initiated at the apical pole. The initiation site of Ca(2+) wave at the apical pole and the pattern of wave propagation were independent of inositol 1,4,5-trisphosphate concentration. Furthermore, a second Ca(2+) wave with the same initiation site and pattern was launched by inhibition of sarco/endoplasmic reticulum Ca(2+)-ATPase pumps of cells continuously stimulated with sub-maximal agonist concentration. By contrast, rapid sequential application of sub-maximal and maximal agonist concentrations to the same cell triggered Ca(2+) waves with different initiation sites. These findings indicate that signaling specificity in pancreatic acinar cells is aided by polarized expression and autonomous functioning of GPCRs and that quantal Ca(2+) release is not due to a partial Ca(2+) release from a continuous pool, but rather, it is due to an all-or-none Ca(2+) release from a compartmentalized Ca(2+) pool.
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Affiliation(s)
- D M Shin
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA
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Abstract
Molecular mechanisms for the regulation of islet amyloid polypeptide (IAPP) gene expression remain unclear. In the present study, we investigated the effects of glucose and forskolin on IAPP gene regulation in the INS-1 islet beta-cell line. Both glucose and forskolin increased the level of expression of this gene, as measured by Northern blot analysis, and increased IAPP gene transcription in a time- and concentration-dependent manner, as demonstrated in a reporter gene assay. Although inhibition of protein kinase A activity with H-89 eliminated the effect of forskolin on this gene, the glucose effect was unaffected. This supported the predominant use of a protein kinase A-independent signaling pathway for glucose regulation of the IAPP gene. Electrophoretic mobility shift assay further indicated that glucose and forskolin regulated expression of this gene by targeting different elements of the promoter. Mutation of the cAMP regulatory element flanking the IAPP coding region resulted in the loss of most of the forskolin-stimulated IAPP gene promoter activity, whereas glucose-enhanced IAPP gene transcription was unaffected. These results demonstrate parallel and distinct regulatory pathways involved in glucose- and forskolin-induced IAPP gene expression in this model beta-cell system.
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Affiliation(s)
- W Q Ding
- Department of Medicine, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Coulie B, Matsuura B, Dong M, Hadac EM, Pinon DI, Feighner SD, Howard AD, Miller LJ. Identification of peptide ligand-binding domains within the human motilin receptor using photoaffinity labeling. J Biol Chem 2001; 276:35518-22. [PMID: 11461914 DOI: 10.1074/jbc.m104489200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [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
The cDNA encoding the human motilin receptor was recently cloned and found to represent a G protein-coupled receptor that is structurally related to the growth hormone secretagogue receptors. Together, these represent a new Class I receptor family. Our aim in the present work is to gain insight into the molecular basis of binding of motilin to its receptor using photoaffinity labeling. To achieve this, we developed a Chinese hamster ovary cell line that overexpressed functional motilin receptor (CHO-MtlR; 175,000 sites per cell, with K(i) = 2.3 +/- 0.4 nm motilin and EC(50) = 0.3 +/- 0.1 nm motilin) and a radioiodinatable peptide analogue of human motilin that incorporated a photolabile p-benzoyl-l-phenylalanine (Bpa) residue into its pharmacophoric domain. This probe, [Bpa(1),Ile(13)]motilin, was a full agonist at the motilin receptor that increased intracellular calcium in a concentration-dependent manner (EC(50) = 1.5 +/- 0.4 nm). This photolabile ligand bound specifically and with high affinity to the motilin receptor (K(i) = 12.4 +/- 1.0 nm), and covalently labeled that molecule within its M(r) = 45,000 deglycosylated core. Cyanogen bromide cleavage demonstrated its covalent attachment to fragments of the receptor having apparent M(r) = 6,000 and M(r) = 31,000. These were demonstrated to represent fragments that included both the first and the large second extracellular loop domains, with the latter representing a unique structural feature of this receptor. The spatial approximation of the pharmacophoric domain of motilin with these receptor domains support their functional importance as well.
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Affiliation(s)
- B Coulie
- Center for Basic Research in Digestive Diseases, Departments of Internal Medicine and Biochemistry/Molecular Biology, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Nardone G, Holicky EL, Uhl JR, Sabatino L, Staibano S, Rocco A, Colantuoni V, Manzo BA, Romano M, Budillon G, Cockerill FR, Miller LJ. In vivo and in vitro studies of cytosolic phospholipase A2 expression in Helicobacter pylori infection. Infect Immun 2001; 69:5857-63. [PMID: 11500464 PMCID: PMC98704 DOI: 10.1128/iai.69.9.5857-5863.2001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2000] [Accepted: 06/11/2001] [Indexed: 02/07/2023] Open
Abstract
Modifications of mucosal phospholipids have been detected in samples from patients with Helicobacter pylori-positive gastritis. These alterations appear secondary to increased phospholipase A2 activity (PLA2). The cytosolic form of this enzyme (cPLA2), normally involved in cellular signaling and growth, has been implicated in cancer pathogenesis. The aim of this study was to investigate cPLA2 expression and PLA2 activity in the gastric mucosae of patients with and without H. pylori infection. In gastric biopsies from 10 H. pylori-positive patients, cPLA2 levels, levels of mRNA as determined by reverse transcriptase PCR, levels of protein as determined by immunohistochemistry, and total PLA2 activity were higher than in 10 H. pylori-negative gastritis patients. To clarify whether H. pylori had a direct effect on the cellular expression of cPLA2, we studied cPLA2 expression in vitro with different human epithelial cell lines, one from a patient with larynx carcinoma (i.e., HEp-2 cells) and two from patients with gastric adenocarcinoma (i.e., AGS and MKN 28 cells), incubated with different H. pylori strains. The levels of cPLA2, mRNA, and protein expression were unchanged in Hep-2 cells independently of cellular adhesion or invasion of the bacteria. Moreover, no change in cPLA2 protein expression was observed in AGS or MKN 28 cells treated with wild-type H. pylori. In conclusion, our study shows increased cPLA2 expression and PLA2 activity in the gastric mucosae of patients with H. pylori infection and no change in epithelial cell lines exposed to H. pylori.
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Affiliation(s)
- G Nardone
- Department of Clinical and Experimental Medicine, Federico II University of Naples, Naples, Italy.
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Ding XQ, Ding WQ, Miller LJ. Receptor biology and signal transduction. Curr Opin Gastroenterol 2001; 17:410-5. [PMID: 17031193 DOI: 10.1097/00001574-200109000-00002] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
This year has witnessed substantial advances in receptor biology and signal transduction that are relevant to the function and regulation of the healthy pancreas and to the pathogenesis and potential therapy of pancreatitis and pancreatic carcinoma. There has been an expansion in the cast of pancreatic regulatory molecules, now including protease-activated receptors, chemokines, and chemokine receptors. There have been new insights into the cellular distribution and signaling initiated at the classic pancreatic receptors. There have also been dramatic advances in insights into the structure of G protein-coupled receptors, with the first solution of a crystal structure of a member of this superfamily, and into the molecular basis of ligand binding and activation of these important molecules. This will clearly improve the opportunities for the rational design and refinement of receptor-active drugs. In addition to these fundamental advances, there has been renewed attention to the expression, function, and regulation of receptors and signaling pathways in pancreatic cells present in the setting of pancreatitis and pancreatic carcinoma. It is hoped that this will contribute toward earlier diagnosis, more successful therapy, and new chemopreventive strategies for these illnesses.
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Affiliation(s)
- X Q Ding
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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31
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Abstract
BACKGROUND & AIMS Islet amyloid polypeptide (IAPP) levels are elevated in pancreatic cancer and may be a useful marker of pancreatic cancer-associated diabetes. The aim of this study was to compare the sensitivity and specificity for pancreatic cancer of IAPP with that of CA19-9, examine clinical characteristics of diabetes in pancreatic cancer, and define the relationship of IAPP to diabetes of pancreatic cancer. METHODS Fasting serum glucose, IAPP, and CA 19-9 were measured in 130 subjects with pancreatic cancer, 250 subjects with other pancreatic and peripancreatic diseases, and 116 controls. In pancreatic cancer patients, we noted tumor stage and the presence and duration of diabetes. RESULTS IAPP was markedly elevated in pancreatic cancer, especially in patients with diabetes. However, the sensitivity of IAPP for pancreatic cancer was less than that of CA 19-9 (40% vs. 75%; P < 0.001). Diabetes was present in 46% of pancreatic cancers and 55% of resectable tumors. In pancreatic cancer with diabetes, the sensitivity of IAPP was only 50%. In resectable cancer it was 27%. CONCLUSIONS IAPP is elevated in pancreatic cancer but is not sensitive enough to replace or complement existing tests. Diabetes occurs early and frequently in pancreatic cancer. Development of a sensitive and specific marker for pancreatic-associated diabetes might lead to diagnosis of resectable pancreatic cancer.
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Affiliation(s)
- S T Chari
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota 55905, USA.
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Holicky EL, Hadac EM, Ding XQ, Miller LJ. Molecular characterization and organ distribution of type A and B cholecystokinin receptors in cynomolgus monkey. Am J Physiol Gastrointest Liver Physiol 2001; 281:G507-14. [PMID: 11447031 DOI: 10.1152/ajpgi.2001.281.2.g507] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [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: 01/31/2023]
Abstract
Differences in the molecular structure or organ distribution of receptors can limit the usefulness of a given species for drug studies. In this work, we have studied cholecystokinin (CCK) receptors in cynomolgus monkey, an animal model useful for preclinical testing. The type A CCK receptor cDNA was cloned and predicted to encode a 428 amino acid peptide that was 98% identical to the human receptor. Only 2 of the 10 residues that were distinct from the human receptor were not present in other cloned CCK receptor species. A Chinese hamster ovary cell line that stably expressed this receptor was developed. The cynomolgus receptor expressed in this environment was functionally indistinguishable from the human receptor, binding CCK with high affinity [inhibition constant (K(I)) = 1.8 +/- 0.5 nM] and exhibiting a potent intracellular calcium signaling response to this hormone (EC(50) = 6.6 +/- 2.1 pM). Like the human type A CCK receptor, this receptor was expressed prominently in monkey gallbladder and stomach and was expressed in low levels in brain and pancreas. The type B CCK receptor cDNA was cloned from stomach and brain (450 residue receptor that is 96% identical to the human receptor), where it was highly expressed yet was undetectable in gallbladder or pancreas. This work confirms the relevance of the cynomolgus species for preclinical testing of drugs acting on the type A CCK receptor.
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Affiliation(s)
- E L Holicky
- Departments of Internal Medicine and Biochemistry/Molecular Biology, Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Abstract
Insights into the molecular basis of binding of the peptide hormone, cholecystokinin, to its G protein-coupled receptor is of substantial interest and may contribute to the successful production and refinement of receptor-active drugs. A number of methodological approaches provide complementary data to contribute to these insights. These include receptor mutagenesis, ligand structure-activity data, conformational analysis of ligand and receptor fragments, and photoaffinity labeling. In this work, we compare and contrast each of these methods and provide our current view of the cumulative impact of the current data on molecular conformational models of the agonist-occupied type A cholecystokinin receptor. These support the key roles played by extracellular loop and tail regions of this receptor for binding its natural peptide ligand.
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Affiliation(s)
- X Q Ding
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, MN 55905, USA
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Miller LJ, Haven CP, McCollum SG, Lee AM, Kamman MR, Baumann DK, Anderson ME, Buderer MC. The International Space Station human life sciences experiment implementation process. Acta Astronaut 2001; 49:477-482. [PMID: 11669134 DOI: 10.1016/s0094-5765(01)00130-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The selection, definition, and development phases of a Life Sciences flight research experiment has been consistent throughout the past decade. The implementation process, however, has changed significantly within the past two years. This change is driven primarily by the shift from highly integrated, dedicated research missions on platforms with well defined processes to self contained experiments with stand alone operations on platforms which are being concurrently designed. For experiments manifested on the International Space Station (ISS) and/or on short duration missions, the more modular, streamlined, and independent the individual experiment is, the more likely it is to be successfully implemented before the ISS assembly is completed. During the assembly phase of the ISS, science operations are lower in priority than the construction of the station. After the station has been completed, it is expected that more resources will be available to perform research. The complexity of implementing investigations increases with the logistics needed to perform the experiment. Examples of logistics issues include- hardware unique to the experiment; large up and down mass and volume needs; access to crew and hardware during the ascent or descent phases; maintenance of hardware and supplies with a limited shelf life,- baseline data collection schedules with lengthy sessions or sessions close to the launch or landing; onboard stowage availability, particularly cold stowage; and extensive training where highly proficient skills must be maintained. As the ISS processes become better defined, experiment implementation will meet new challenges due to distributed management, on-orbit resource sharing, and adjustments to crew availability pre- and post-increment.
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Affiliation(s)
- L J Miller
- NASA Johnson Space Center, Houston, Texas, USA
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Jiang SW, Dong M, Trujillo MA, Miller LJ, Eberhardt NL. DNA binding of TEA/ATTS domain factors is regulated by protein kinase C phosphorylation in human choriocarcinoma cells. J Biol Chem 2001; 276:23464-70. [PMID: 11313339 DOI: 10.1074/jbc.m010934200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [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: 11/06/2022] Open
Abstract
Transcription enhancer factor 1 (TEF-1) controls the expression of a diverse set of genes. Previous studies implicated protein kinase C (PKC)-mediated signal transduction in modulating TEF function. We demonstrate that in human choriocarcinoma BeWo cells, the PKC activator 12-O-tetradecanoyl phorbol 13-acetate and PKC inhibitor bisindolylmaleimide reciprocally down- and up-regulate, respectively, TEF-mediated GGAATG core enhancer activity. In vitro TEF-1 phosphorylation with several PKC isozymes and phosphoamino acid analysis confirmed that TEF-1 is a potential PKC substrate. TEF-1.DNA complexes formed by BeWo nuclear extracts are supershifted by phosphoserine- and phosphothreonine- but not phosphotyrosine-specific antibodies, indicating that TEF-1 is phosphorylated in vivo at serine and threonine residues. The TEF-1 phosphorylation domain was localized to the third alpha-helix of the DNA binding domain and adjacent hinge region by phosphopeptide analysis. TEF-1 phosphorylation significantly reduced its DNA binding activity both in vitro and in vivo, providing a possible mechanism for the inhibitory action of PKC. Finally, BeWo cells contained abundant levels of gamma and delta PKC isoforms, and their overexpression resulted in even greater inhibition of GGAATG core enhancer activity after 12-O-tetradecanoyl phorbol 13-acetate treatment. These data strongly suggest that PKC-mediated phosphorylation is a key factor controlling TEF function.
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Affiliation(s)
- S W Jiang
- Department of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
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Mangeot SD, Miller LJ, McIntosh DN, McGrath-Clarke J, Simon J, Hagerman RJ, Goldson E. Sensory modulation dysfunction in children with attention-deficit-hyperactivity disorder. Dev Med Child Neurol 2001; 43:399-406. [PMID: 11409829 DOI: 10.1017/s0012162201000743] [Citation(s) in RCA: 183] [Impact Index Per Article: 8.0] [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: 11/07/2022]
Abstract
This study investigates the presence of sensory modulation dysfunction (SMD) among children with attention-deficit-hyperactivity disorder (ADHD). Twenty-six children with ADHD (mean age 8.3 years, 18 males, 8 females), and 30 typically developing children (mean age 8.2 years, 21 males, 9 females) were tested using a laboratory procedure that gauges responses to repeated sensory stimulation by measuring electrodermal reactivity (EDR). Parental report measures of limitations in sensory, emotional, and attentional dimensions were administered using the Short Sensory Profile, the Leiter International Performance Scale-Revised, Parent Rating subscales, and the Child Behavior Checklist (CBCL). Compared to the typical sample, the children with ADHD displayed greater abnormalities in sensory modulation on both physiological and parent-report measures. The children with ADHD also displayed more variability in responses. Within the group with ADHD, levels of SMD were highly correlated with measures of psychopathology on the CBCL. Implications of findings relate to the importance of considering sensory processing abilities in a subgroup of children with ADHD.
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Affiliation(s)
- S D Mangeot
- Graduate School of Professional Psychology, University of Denver, Colorado, USA
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Abstract
OBJECTIVES This study examined the relationship between insight into mental illness and current child maltreatment risk among mothers who had a major psychiatric disorder and who had lost custody of a child because of abuse, neglect, or having placed the child at risk of harm. Specifically, a measure of insight was examined in relation to systematically observed parenting behaviors known to be correlated with past child maltreatment and in relation to a comprehensive clinical determination of risk. METHODS Forty-four mothers who had a major psychiatric disorder were independently rated for their insight into their illness, the quality of mother-child interaction, and the overall clinical risk of maltreatment. RESULTS Better insight into mental illness was associated with more sensitive mothering behavior and with lower assessed clinical risk of maltreatment. The association remained when mothers with current psychotic symptoms were excluded from the analyses. Better insight did not appear to be associated with past psychotic symptoms, maternal psychiatric diagnosis, or the mother's level of education. CONCLUSIONS Insight into mental illness may function as a protective factor that influences the risk of child maltreatment in mothers with mental illness. Measures of insight could be usefully incorporated into comprehensive parenting assessments for mothers with psychiatric disorders.
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Affiliation(s)
- M Mullick
- Department of Psychiatry, University of Illinois at Chicago, 60612, USA.
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Abstract
BACKGROUND Controversy persists regarding the reasons for persistent subjective complaints after mild traumatic head injury (THI). STATEMENT OF PURPOSE To evaluate the influence of injury severity, psychological factors, and financial contingencies on symptomatology after THI. METHODS Subjective complaints about cognitive, emotional, and somatic symptoms, as assessed by a standardized self-report inventory (Minnesota Multiphasic Personality Inventory-2; MMPI-2) were evaluated in 150 patients with THI. RESULTS Individuals with mild THI demonstrated paradoxically greater symptomatology on the MMPI-2 than patients with moderate-to-severe THI. Furthermore, specific actuarial criteria for possible symptom magnification (Fake Bad Scale) were met about twice as often in patients with mild THI who were seeking financial compensation for alleged acquired dysfunction than in patients with mild THI without such external contingencies. CONCLUSION The evaluation of persistent subjective complaints after THI should consider injury severity in concert with psychological and financial/motivational factors. Great caution should be taken in attributing persistent symptomatology after mild THI to cerebral dysfunction.
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Affiliation(s)
- L J Miller
- Psychology Service, Mary Free Bed Hospital, Grand Rapids, MI, USA
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Abstract
OBJECTIVE To report the use of gabapentin in the treatment of behavioral and psychological symptoms of dementia (BPSD) and to review the available literature relating to the use of gabapentin in this population. CASE SUMMARY A 62-year-old white man was admitted to the hospital due to a worsening state of confusion, anxiety, depressed mood, insomnia, and verbal and physical aggressiveness toward his wife. He had a past medical history significant for vascular dementia. He had been intolerant of or had failed to respond to numerous antidepressants, benzodiazepines, and neuroleptics. The addition of gabapentin to the patient's medication regimen resulted in reduced agitation, sexual inappropriateness, and lability. He was discharged to his home on a dose of gabapentin 300 mg three times daily. DATA SOURCES A MEDLINE search (1966-August 2000) was performed to identify case reports and clinical trials discussing the efficacy of gabapentin in the treatment of BPSD. DISCUSSION Gabapentin, like other anticonvulsants, has been used with success in several psychiatric illnesses. Available literature indicates that the drug may have some efficacy in the treatment of BPSD. It has a favorable adverse effect profile in the elderly, which makes it an attractive altemative to standard therapies, including benzodiazepines and neuroleptics. Optimal dosing remains unclear. CONCLUSIONS This case suggests that gabapentin is a reasonable alternative therapy for patients whose behavioral symptoms do not respond to conventional agents.
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Affiliation(s)
- L J Miller
- Memorial Hermann Southwest Hospital, Houston, TX 77074-1802, USA.
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Abstract
Structural analysis of secretin in solution has demonstrated extended helical domains within both amino- and carboxyl-terminal halves, with a possible turn in between. However, the conformation of this peptide as it resides in its binding site within the receptor has not been established. In the work reported here, we performed affinity labeling of the secretin receptor with radioiodinated secretin analogues having photolabile benzoyl-phenylalanine residues positioned in each half of the peptide. The probes had sites of covalent attachment in positions 6 and 22, and have been recently synthesized and characterized to represent high affinity agonist ligands. Both covalently labeled the secretin receptor in a saturable, specific, and efficient manner. After purification of the labeled receptor, we used a series of chemical and enzymatic cleavage techniques to define the domain of labeling. We complemented this by receptor mutagenesis, followed by additional cleavage and Edman degradation sequencing to refine our insights into the labeled residues. This has allowed us to demonstrate that sites of attachment were both within the extracellular aminoterminal domain of the receptor. Of particular interest, both probes labeled residues within the amino-terminal thirty residues at the distal end of the receptor. It will be particularly interesting to use these molecular approximations to model the binding domain of this important receptor.
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Affiliation(s)
- M Dong
- Center for Basic Research in Digestive Diseases, Mayo Clinic, Rochester, Minnesota 55905, USA
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41
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Ding XQ, Dolu V, Hadac EM, Holicky EL, Pinon DI, Lybrand TP, Miller LJ. Refinement of the structure of the ligand-occupied cholecystokinin receptor using a photolabile amino-terminal probe. J Biol Chem 2001; 276:4236-44. [PMID: 11050076 DOI: 10.1074/jbc.m003798200] [Citation(s) in RCA: 41] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Affinity labeling is a powerful tool to establish spatial approximations between photolabile residues within a ligand and its receptor. Here, we have utilized a cholecystokinin (CCK) analogue with a photolabile benzoylphenylalanine (Bpa) sited in position 24, adjacent to the pharmacophoric domain of this hormone (positions 27-33). This probe was a fully efficacious agonist that bound to the CCK receptor saturably and with high affinity (K(i) = 8.9 +/- 1.1 nm). It covalently labeled the CCK receptor either within the amino terminus (between Asn(10) and Lys(37)) or within the third extracellular loop (Glu(345)), as demonstrated by proteolytic peptide mapping, deglycosylation, micropurification, and Edman degradation sequencing. Truncation of the receptor to eliminate residues 1-30 had no detrimental effect on CCK binding, stimulated signaling, or affinity labeling through a residue within the pharmacophore (Bpa(29)) but resulted in elimination of the covalent attachment of the Bpa(24) probe to the receptor. Thus, the distal amino terminus of the CCK receptor resides above the docked ligand, compressing the portion of the peptide extending beyond its pharmacophore toward the receptor core. Exposure of wild type and truncated receptor constructs to extracellular trypsin damaged the truncated construct but not the wild type receptor, suggesting that this domain also may play a protective role. Use of these additional insights into molecular approximations provided key constraints for molecular modeling of the peptide-receptor complex, supporting the counterclockwise organization of the transmembrane helical domains.
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Affiliation(s)
- X Q Ding
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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42
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Abstract
Secretin not only increases ductular bile secretion in vivo in rats after bile duct ligation (BDL) [1], but also increases cAMP levels and stimulates exocytosis in isolated cholangiocytes [2]. Although we have previously reported that secretin receptor mRNA was upregulated in cholangiocytes after BDL [3], the cholangiocyte secretin receptor has not been functionally characterized or quantified after BDL. In this work, we used a novel, photolabile and biologically active analogue of secretin to quantify and characterize secretin receptors on cholangiocytes isolated from normal and BDL rats. The cholangiocyte secretin receptor bound radioligand with high affinity and in a rapid, reversible, and temperature-dependent manner. While receptors on cholangiocytes from normal and BDL rats were functionally and biochemically identical, receptor density on cholangiocytes was increased 5-fold following BDL. The combination of increased cell number with increased functional secretin receptors per cell is due to the fact that cholangiocyte hyperplasia represents a reactive response to a cholestatic condition and this effort on the part of the organism to maintain bile secretion, explains the increased hormone-responsive choleresis observed after BDL and may reflect an adaptive response of the organism to cholestasis.
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Affiliation(s)
- P S Tietz
- Center for Basic Research in Digestive Diseases, Mayo Medical School, Clinic and Foundation, Rochester, MN 55905, USA
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43
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44
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Ding XQ, Rao RV, Kuntz SM, Holicky EL, Miller LJ. Impaired resensitization and recycling of the cholecystokinin receptor by co-expression of its second intracellular loop. Mol Pharmacol 2000; 58:1424-33. [PMID: 11093782 DOI: 10.1124/mol.58.6.1424] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [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: 11/22/2022] Open
Abstract
Intermolecular interaction represents an important theme in regulation of intracellular trafficking of organelles that can be interrupted by competitive overexpression of a relevant molecular domain. We attempted to identify the functional importance of intracellular domains of the cholecystokinin (CCK) receptor by their over-expression in receptor-bearing Chinese hamster ovary (CHO-CCKR) cell lines. Although clathrin-dependent endocytosis and recycling of this receptor are well-established (J Cell Biol 128:1029-1042, 1995), any influence of distinct receptor domains is not understood. In this work, constructs representing each of the intracellular domains of the CCK receptor were coexpressed with wild-type receptor, and stable clonal cell lines were selected. Each was characterized for ligand binding and agonist-stimulated biological activity (inositol 1,4,5-trisphosphate generation), desensitization, resensitization, receptor internalization, and recycling. Each cell line expressed normal CCK radioligand binding, signaling, internalization, and desensitization. Three independent cell lines that coexpressed the 25-residue second intracellular loop domain exhibited deficient resensitization. In morphological assessment of receptor trafficking, this construct was also shown to interfere with receptor recycling to the plasma membrane. As a control, recycling of an unrelated G protein-coupled receptor was demonstrated to occur normally in this cell line. These observations suggest that rather than representing passive cargo within an endosome, a receptor can influence its own trafficking within the cell.
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Affiliation(s)
- X Q Ding
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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45
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Rao RV, Holicky EL, Kuntz SM, Miller LJ. CCK receptor phosphorylation exposes regulatory domains affecting phosphorylation and receptor trafficking. Am J Physiol Cell Physiol 2000; 279:C1986-92. [PMID: 11078715 DOI: 10.1152/ajpcell.2000.279.6.c1986] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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: 11/22/2022]
Abstract
Agonist-stimulated phosphorylation of guanine nucleotide-binding protein (G protein)-coupled receptors has been recognized as an important mechanism for desensitization by interfering with coupling of the activated receptor with its G protein. We recently described a mutant of the CCK receptor that modified two of five key sites of phosphorylation (S260,264A) and eliminated agonist-stimulated receptor phosphorylation, despite normal ligand binding and signaling (20). As expected, this nonphosphorylated mutant had impaired rapid desensitization but was ultimately able to be desensitized by normal receptor internalization. Here we demonstrate that this mutant receptor is also defective in resensitization, with abnormal recycling to the cell surface. To explore this, another receptor mutant was prepared, replacing the same serines with aspartates to mimic the charge of serine-phosphate (S260,264D). This mutant was expressed in a Chinese hamster ovary cell line and shown to bind CCK normally. It had accelerated kinetics of signaling and desensitization and was phosphorylated in response to agonist occupation, with all other normal sites of phosphorylation modified. It was internalized like wild-type receptors and was resensitized and trafficked normally. This provides evidence for an additional important function for phosphorylation of G protein-coupled receptors. Phosphorylation may induce a conformational change in the receptor to expose other potential sites of phosphorylation and to expose domains involved in the targeting and trafficking of endosomes. The hierarchical phosphorylation of these sites may play a key role in receptor regulation.
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Affiliation(s)
- R V Rao
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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46
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Affiliation(s)
- L J Miller
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, MN 55905, USA.
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47
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Asmann YW, Dong M, Ganguli S, Hadac EM, Miller LJ. Structural insights into the amino-terminus of the secretin receptor: I. Status of cysteine and cystine residues. Mol Pharmacol 2000; 58:911-9. [PMID: 11040037 DOI: 10.1124/mol.58.5.911] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [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: 11/22/2022] Open
Abstract
The secretin receptor is prototypic of the class II family of G protein-coupled receptors, with a long extracellular amino-terminal domain containing six highly conserved Cys residues and one Cys residue (Cys(11)) that is present only in the most closely related family members. This domain is critical for function, with some component Cys residues believed to be involved in key disulfide bonds, although these have never been directly demonstrated. Here, we examine the functional importance of each of these residues and determine their involvement in disulfide bonds. Secretin binding was markedly diminished after treating cells with cell-impermeant reducing reagents, supporting the presence of important extracellular disulfide bonds. To determine whether the amino-terminal domain was covalently attached to the receptor body by disulfide linkage, a strategy was implemented that involved introduction of an acid-labile Asp-Pro sequence to enable specific cleavage at the boundary of these domains. Under nonreducing conditions, the amino terminus was released from the receptor body, supporting the absence of covalent association between these domains. Quantitative [(14)C]iodoacetamide incorporation into the isolated amino-terminal domain of the receptor in the absence and presence of chemical reduction established the ratio of free to total Cys residues as 1:7, consistent with three disulfide bonds. Mutagenesis of each of the amino-terminal Cys residues to Ala was tolerated only for Cys(11), suggesting that these bonds linked the conserved Cys residues. This was further supported by treatment of intact cells expressing wild-type or C11A mutant secretin receptor with a cell-impermeant sulfhydryl-reactive reagent. Thus, the functionally important amino terminus of the secretin receptor represents a structurally independent, highly folded, and disulfide-bonded domain, with a pattern that is likely critical and conserved throughout this receptor family.
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Affiliation(s)
- Y W Asmann
- Center for Basic Research in Digestive Diseases, Department of Internal Medicine and Biochemistry/Molecular Biology, Mayo Clinic and Foundation, Rochester, Minnesota, USA
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48
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Park CG, Ganguli SC, Pinon DI, Hadac EM, Miller LJ. Cross-chimeric analysis of selectivity of secretin and VPAC(1) receptor activation. J Pharmacol Exp Ther 2000; 295:682-8. [PMID: 11046106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Agonist action at receptors is highly specific, affected by the structure of both ligand and receptor. Chimeric constructs of structurally related receptors and/or ligands that have biological differences provide an opportunity to correlate a specific structural domain with function. In this work, we have used a cross-chimeric approach to explore the structural basis for rat secretin and vasoactive intestinal polypeptide action at their closely related secretin and VPAC(1) receptors, belonging to class II of the G protein-coupled receptor superfamily. Multiple domains of both ligands and receptors contributed toward their selectivity, with differing combinations of such domains able to support high-potency interactions. The amino-terminal 15 residues of secretin were most critical for potent stimulation of secretin receptors, whereas either the amino- or carboxyl-terminal halves of vasoactive intestinal polypeptide, when complemented by Lys(15), provided potent stimulation of the VPAC(1) receptor. The amino terminus of the VPAC(1) receptor was most critical for potent response to vasoactive intestinal polypeptide, whereas the amino terminus of the secretin receptor was important, but not adequate, requiring the complementation of an extracellular loop domain for potent response to secretin. Differences in the distribution of these determinants within these receptors provided an opportunity to produce a more "universal" receptor that contained the first extracellular loop of the secretin receptor and the remainder of the VPAC(1) receptor. This cross-chimeric approach should be applied to other members of this receptor family to test the emerging themes and to expand these insights as broadly as possible.
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Affiliation(s)
- C G Park
- Center for Basic Research in Digestive Diseases, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic and Foundation, Rochester, Minnesota, USA
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49
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Ferrer FA, Pantschenko AG, Miller LJ, Anderson K, Grunnet M, McKenna PH, Kreutzer D. Angiogenesis and neuroblastomas: interleukin-8 and interleukin-8 receptor expression in human neuroblastoma. J Urol 2000. [PMID: 10958731 DOI: 10.1016/s0022-5347(05)67240-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Studies have demonstrated that the pro-angiogenic cytokine interleukin-8 (IL-8) and the IL-8 receptors likely have a role in the growth and metastasis of various solid tumors. We hypothesized that in vivo neuroblastoma expresses IL-8 and the IL-8 receptors A and B, and that factors known to regulate IL-8 expression are present and active in the neuroblastoma microenvironment. MATERIALS AND METHODS To confirm the presence of IL-8/IL-8 receptors in neuroblastoma, immunohistochemical analysis for IL-8 and its receptors was performed on 10 archival specimens, including benign adrenal and well to poorly differentiated neuroblastoma samples. Immunohistochemical analysis was also performed for interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha. Cultured neuroblastoma cells SK-N-MC and SK-N-SH were stimulated with 10 ng./ml. IL-1beta or tumor necrosis factor-alpha and control media (15 each). Cell culture supernatants were analyzed with enzyme-linked immunosorbant assay for IL-8 levels at 24 and 48 hours. RESULTS Minimal expression of IL-8 was noted in benign adrenal tissue but expression for IL-8 was present in all neuroblastoma specimens. Microvessel staining was present in 30% of the specimens. All tumor specimens expressed IL-8 receptor B, and both receptors were expressed in the tumor microvasculature. Immunohistochemical analysis confirmed the presence of IL-1beta and tumor necrosis factor in the neuroblastoma microenvironment. In vitro studies demonstrated that SK-N-MC and SK-N-SH cells express low levels of IL-8 under normal conditions and that IL-1beta and tumor necrosis factor-alpha significantly increased expression of IL-8 at 24 and 48 hours. CONCLUSIONS Our results indicate that IL-8 and its receptors are expressed in neuroblastoma tumor specimens. In addition, the fact that IL-1beta and tumor necrosis factor-alpha are expressed in the neuroblastoma microenvironment combined with our in vitro results suggests that these cytokines may be involved in in vivo regulation of IL-8 in human neuroblastoma. Understanding the angiogenic factors and regulatory cascade promoting angiogensis in neuroblastoma may lead to the development of effective anti-angiogenic strategies.
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Affiliation(s)
- F A Ferrer
- Department of Pediatric Urology, The Connecticut Children's Medical Center, Hartford, Connecticut 06106, USA
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Ferrer FA, Pantschenko AG, Miller LJ, Anderson K, Grunnet M, McKenna PH, Kreutzer D. Angiogenesis and neuroblastomas: interleukin-8 and interleukin-8 receptor expression in human neuroblastoma. J Urol 2000; 164:1016-20. [PMID: 10958731 DOI: 10.1097/00005392-200009020-00024] [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: 11/27/2022]
Abstract
PURPOSE Studies have demonstrated that the pro-angiogenic cytokine interleukin-8 (IL-8) and the IL-8 receptors likely have a role in the growth and metastasis of various solid tumors. We hypothesized that in vivo neuroblastoma expresses IL-8 and the IL-8 receptors A and B, and that factors known to regulate IL-8 expression are present and active in the neuroblastoma microenvironment. MATERIALS AND METHODS To confirm the presence of IL-8/IL-8 receptors in neuroblastoma, immunohistochemical analysis for IL-8 and its receptors was performed on 10 archival specimens, including benign adrenal and well to poorly differentiated neuroblastoma samples. Immunohistochemical analysis was also performed for interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha. Cultured neuroblastoma cells SK-N-MC and SK-N-SH were stimulated with 10 ng./ml. IL-1beta or tumor necrosis factor-alpha and control media (15 each). Cell culture supernatants were analyzed with enzyme-linked immunosorbant assay for IL-8 levels at 24 and 48 hours. RESULTS Minimal expression of IL-8 was noted in benign adrenal tissue but expression for IL-8 was present in all neuroblastoma specimens. Microvessel staining was present in 30% of the specimens. All tumor specimens expressed IL-8 receptor B, and both receptors were expressed in the tumor microvasculature. Immunohistochemical analysis confirmed the presence of IL-1beta and tumor necrosis factor in the neuroblastoma microenvironment. In vitro studies demonstrated that SK-N-MC and SK-N-SH cells express low levels of IL-8 under normal conditions and that IL-1beta and tumor necrosis factor-alpha significantly increased expression of IL-8 at 24 and 48 hours. CONCLUSIONS Our results indicate that IL-8 and its receptors are expressed in neuroblastoma tumor specimens. In addition, the fact that IL-1beta and tumor necrosis factor-alpha are expressed in the neuroblastoma microenvironment combined with our in vitro results suggests that these cytokines may be involved in in vivo regulation of IL-8 in human neuroblastoma. Understanding the angiogenic factors and regulatory cascade promoting angiogensis in neuroblastoma may lead to the development of effective anti-angiogenic strategies.
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Affiliation(s)
- F A Ferrer
- Department of Pediatric Urology, The Connecticut Children's Medical Center, Hartford, Connecticut 06106, USA
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