TY  - JOUR
A1  - Tiegs, Scott D.
A1  - Costello, David M.
A1  - Isken, Mark W.
A1  - Woodward, Guy
A1  - McIntyre, Peter B.
A1  - Gessner, Mark O.
A1  - Chauvet, Eric
A1  - Griffiths, Natalie A.
A1  - Flecker, Alex S.
A1  - Acuna, Vicenc
A1  - Albarino, Ricardo
A1  - Allen, Daniel C.
A1  - Alonso, Cecilia
A1  - Andino, Patricio
A1  - Arango, Clay
A1  - Aroviita, Jukka
A1  - Barbosa, Marcus V. M.
A1  - Barmuta, Leon A.
A1  - Baxter, Colden V.
A1  - Bell, Thomas D. C.
A1  - Bellinger, Brent
A1  - Boyero, Luz
A1  - Brown, Lee E.
A1  - Bruder, Andreas
A1  - Bruesewitz, Denise A.
A1  - Burdon, Francis J.
A1  - Callisto, Marcos
A1  - Canhoto, Cristina
A1  - Capps, Krista A.
A1  - Castillo, Maria M.
A1  - Clapcott, Joanne
A1  - Colas, Fanny
A1  - Colon-Gaud, Checo
A1  - Cornut, Julien
A1  - Crespo-Perez, Veronica
A1  - Cross, Wyatt F.
A1  - Culp, Joseph M.
A1  - Danger, Michael
A1  - Dangles, Olivier
A1  - de Eyto, Elvira
A1  - Derry, Alison M.
A1  - Diaz Villanueva, Veronica
A1  - Douglas, Michael M.
A1  - Elosegi, Arturo
A1  - Encalada, Andrea C.
A1  - Entrekin, Sally
A1  - Espinosa, Rodrigo
A1  - Ethaiya, Diana
A1  - Ferreira, Veronica
A1  - Ferriol, Carmen
A1  - Flanagan, Kyla M.
A1  - Fleituch, Tadeusz
A1  - Shah, Jennifer J. Follstad
A1  - Frainer, Andre
A1  - Friberg, Nikolai
A1  - Frost, Paul C.
A1  - Garcia, Erica A.
A1  - Lago, Liliana Garcia
A1  - Garcia Soto, Pavel Ernesto
A1  - Ghate, Sudeep
A1  - Giling, Darren P.
A1  - Gilmer, Alan
A1  - Goncalves, Jose Francisco
A1  - Gonzales, Rosario Karina
A1  - Graca, Manuel A. S.
A1  - Grace, Mike
A1  - Grossart, Hans-Peter
A1  - Guerold, Francois
A1  - Gulis, Vlad
A1  - Hepp, Luiz U.
A1  - Higgins, Scott
A1  - Hishi, Takuo
A1  - Huddart, Joseph
A1  - Hudson, John
A1  - Imberger, Samantha
A1  - Iniguez-Armijos, Carlos
A1  - Iwata, Tomoya
A1  - Janetski, David J.
A1  - Jennings, Eleanor
A1  - Kirkwood, Andrea E.
A1  - Koning, Aaron A.
A1  - Kosten, Sarian
A1  - Kuehn, Kevin A.
A1  - Laudon, Hjalmar
A1  - Leavitt, Peter R.
A1  - Lemes da Silva, Aurea L.
A1  - Leroux, Shawn J.
A1  - Leroy, Carri J.
A1  - Lisi, Peter J.
A1  - MacKenzie, Richard
A1  - Marcarelli, Amy M.
A1  - Masese, Frank O.
A1  - Mckie, Brendan G.
A1  - Oliveira Medeiros, Adriana
A1  - Meissner, Kristian
A1  - Milisa, Marko
A1  - Mishra, Shailendra
A1  - Miyake, Yo
A1  - Moerke, Ashley
A1  - Mombrikotb, Shorok
A1  - Mooney, Rob
A1  - Moulton, Tim
A1  - Muotka, Timo
A1  - Negishi, Junjiro N.
A1  - Neres-Lima, Vinicius
A1  - Nieminen, Mika L.
A1  - Nimptsch, Jorge
A1  - Ondruch, Jakub
A1  - Paavola, Riku
A1  - Pardo, Isabel
A1  - Patrick, Christopher J.
A1  - Peeters, Edwin T. H. M.
A1  - Pozo, Jesus
A1  - Pringle, Catherine
A1  - Prussian, Aaron
A1  - Quenta, Estefania
A1  - Quesada, Antonio
A1  - Reid, Brian
A1  - Richardson, John S.
A1  - Rigosi, Anna
A1  - Rincon, Jose
A1  - Risnoveanu, Geta
A1  - Robinson, Christopher T.
A1  - Rodriguez-Gallego, Lorena
A1  - Royer, Todd V.
A1  - Rusak, James A.
A1  - Santamans, Anna C.
A1  - Selmeczy, Geza B.
A1  - Simiyu, Gelas
A1  - Skuja, Agnija
A1  - Smykla, Jerzy
A1  - Sridhar, Kandikere R.
A1  - Sponseller, Ryan
A1  - Stoler, Aaron
A1  - Swan, Christopher M.
A1  - Szlag, David
A1  - Teixeira-de Mello, Franco
A1  - Tonkin, Jonathan D.
A1  - Uusheimo, Sari
A1  - Veach, Allison M.
A1  - Vilbaste, Sirje
A1  - Vought, Lena B. M.
A1  - Wang, Chiao-Ping
A1  - Webster, Jackson R.
A1  - Wilson, Paul B.
A1  - Woelfl, Stefan
A1  - Xenopoulos, Marguerite A.
A1  - Yates, Adam G.
A1  - Yoshimura, Chihiro
A1  - Yule, Catherine M.
A1  - Zhang, Yixin X.
A1  - Zwart, Jacob A.
T1  - Global patterns and drivers of ecosystem functioning in rivers and riparian zones
JF  - Science Advances
N2  - River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth’s biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented “next-generation biomonitoring” by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.
Y1  - 2019
U6  - https://doi.org/10.1126/sciadv.aav0486
SN  - 2375-2548
VL  - 5
IS  - 1
PB  - American Assoc. for the Advancement of Science
CY  - Washington
ER  - 
TY  - JOUR
A1  - von Loeffelholz, Christian
A1  - Lieske, Stefanie
A1  - Neuschaefer-Rube, Frank
A1  - Willmes, Diana M.
A1  - Raschzok, Nathanael
A1  - Sauer, Igor M.
A1  - König, Jörg
A1  - Fromm, Martin F.
A1  - Horn, Paul
A1  - Chatzigeorgiou, Antonios
A1  - Pathe-Neuschaefer-Rube, Andrea
A1  - Jordan, Jens
A1  - Pfeiffer, Andreas F. H.
A1  - Mingrone, Geltrude
A1  - Bornstein, Stefan R.
A1  - Stroehle, Peter
A1  - Harms, Christoph
A1  - Wunderlich, F. Thomas
A1  - Helfand, Stephen L.
A1  - Bernier, Michel
A1  - de Cabo, Rafael
A1  - Shulman, Gerald I.
A1  - Chavakis, Triantafyllos
A1  - Püschel, Gerhard Paul
A1  - Birkenfeld, Andreas L.
T1  - The human longevity gene homolog INDY and interleukin-6 interact in hepatic lipid metabolism
BT  - official journal of the American Association for the Study of Liver Diseases
JF  - Hepatology
N2  - Reduced expression of the Indy ("I am Not Dead, Yet") gene in lower organisms promotes longevity in a manner akin to caloric restriction. Deletion of the mammalian homolog of Indy (mIndy, Slc13a5) encoding for a plasma membrane-associated citrate transporter expressed highly in the liver, protects mice from high-fat diet-induced and aging-induced obesity and hepatic fat accumulation through a mechanism resembling caloric restriction. We studied a possible role of mIndy in human hepatic fat metabolism. In obese, insulin-resistant patients with nonalcoholic fatty liver disease, hepatic mIndy expression was increased and mIndy expression was also independently associated with hepatic steatosis. In nonhuman primates, a 2-year high-fat, high-sucrose diet increased hepatic mIndy expression. Liver microarray analysis showed that high mIndy expression was associated with pathways involved in hepatic lipid metabolism and immunological processes. Interleukin-6 (IL-6) was identified as a regulator of mIndy by binding to its cognate receptor. Studies in human primary hepatocytes confirmed that IL-6 markedly induced mIndy transcription through the IL-6 receptor and activation of the transcription factor signal transducer and activator of transcription 3, and a putative start site of the human mIndy promoter was determined. Activation of the IL-6-signal transducer and activator of transcription 3 pathway stimulated mIndy expression, enhanced cytoplasmic citrate influx, and augmented hepatic lipogenesis in vivo. In contrast, deletion of mIndy completely prevented the stimulating effect of IL-6 on citrate uptake and reduced hepatic lipogenesis. These data show that mIndy is increased in liver of obese humans and nonhuman primates with NALFD. Moreover, our data identify mIndy as a target gene of IL-6 and determine novel functions of IL-6 through mINDY. Conclusion: Targeting human mINDY may have therapeutic potential in obese patients with nonalcoholic fatty liver disease. German Clinical Trials Register: DRKS00005450.
Y1  - 2017
U6  - https://doi.org/10.1002/hep.29089
SN  - 0270-9139
SN  - 1527-3350
VL  - 66
IS  - 2
SP  - 616
EP  - 630
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Frodl, Thomas
A1  - Janowitz, Deborah
A1  - Schmaal, Lianne
A1  - Tozzi, Leonardo
A1  - Dobrowolny, Henrik
A1  - Stein, Dan J.
A1  - Veltman, Dick J.
A1  - Wittfeld, Katharina
A1  - van Erp, Theo G. M.
A1  - Jahanshad, Neda
A1  - Block, Andrea
A1  - Hegenscheid, Katrin
A1  - Voelzke, Henry
A1  - Lagopoulos, Jim
A1  - Hatton, Sean N.
A1  - Hickie, Ian B.
A1  - Frey, Eva Maria
A1  - Carballedo, Angela
A1  - Brooks, Samantha J.
A1  - Vuletic, Daniella
A1  - Uhlmann, Anne
A1  - Veer, Ilya M.
A1  - Walter, Henrik
A1  - Schnell, Knut
A1  - Grotegerd, Dominik
A1  - Arolt, Volker
A1  - Kugel, Harald
A1  - Schramm, Elisabeth
A1  - Konrad, Carsten
A1  - Zurowski, Bartosz
A1  - Baune, Bernhard T.
A1  - van der Wee, Nic J. A.
A1  - van Tol, Marie-Jose
A1  - Penninx, Brenda W. J. H.
A1  - Thompson, Paul M.
A1  - Hibar, Derrek P.
A1  - Dannlowski, Udo
A1  - Grabe, Hans J.
T1  - Childhood adversity impacts on brain subcortical structures relevant to depression
JF  - Journal of psychiatric research
N2  - Childhood adversity plays an important role for development of major depressive disorder (MDD). There are differences in subcortical brain structures between patients with MDD and healthy controls, but the specific impact of childhood adversity on such structures in MDD remains unclear. Thus, aim of the present study was to investigate whether childhood adversity is associated with subcortical volumes and how it interacts with a diagnosis of MDD and sex. Within the ENIGMA-MDD network, nine university partner sites, which assessed childhood adversity and magnetic resonance imaging in patients with MDD and controls, took part in the current joint mega-analysis. In this largest effort world-wide to identify subcortical brain structure differences related to childhood adversity, 3036 participants were analyzed for subcortical brain volumes using FreeSurfer. A significant interaction was evident between childhood adversity, MDD diagnosis, sex, and region. Increased exposure to childhood adversity was associated with smaller caudate volumes in females independent of MDD. All subcategories of childhood adversity were negatively associated with caudate volumes in females - in particular emotional neglect and physical neglect (independently from age, ICV, imaging site and MDD diagnosis). There was no interaction effect between childhood adversity and MDD diagnosis on subcortical brain volumes. Childhood adversity is one of the contributors to brain structural abnormalities. It is associated with subcortical brain abnormalities that are relevant to psychiatric disorders such as depression. (C) 2016 Published by Elsevier Ltd.
KW  - Depression
KW  - Childhood adversity
KW  - MRI
KW  - Caudate
KW  - Hippocampus
KW  - ENIGMA
Y1  - 2016
U6  - https://doi.org/10.1016/j.jpsychires.2016.11.010
SN  - 0022-3956
SN  - 1879-1379
VL  - 86
SP  - 58
EP  - 65
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Creighton, Andrea L.
A1  - Parsekian, Andrew D.
A1  - Angelopoulos, Michael
A1  - Jones, Benjamin M.
A1  - Bondurant, A.
A1  - Engram, M.
A1  - Lenz, Josefine
A1  - Overduin, Pier Paul
A1  - Grosse, Guido
A1  - Babcock, E.
A1  - Arp, Christopher D.
T1  - Transient Electromagnetic Surveys for the Determination of Talik Depth and Geometry Beneath Thermokarst Lakes
JF  - Journal of geophysical research : Solid earth
N2  - Thermokarst lakes are prevalent in Arctic coastal lowland regions and sublake permafrost degradation and talik development contributes to greenhouse gas emissions by tapping the large permafrost carbon pool. Whereas lateral thermokarst lake expansion is readily apparent through remote sensing and shoreline measurements, sublake thawed sediment conditions and talik growth are difficult to measure. Here we combine transient electromagnetic surveys with thermal modeling, backed up by measured permafrost properties and radiocarbon ages, to reveal closed-talik geometry associated with a thermokarst lake in continuous permafrost. To improve access to talik geometry data, we conducted surveys along three transient electromagnetic transects perpendicular to lakeshores with different decadal-scale expansion rates of 0.16, 0.38, and 0.58m/year. We modeled thermal development of the talik using boundary conditions based on field data from the lake, surrounding permafrost and a borehole, independent of the transient electromagnetics. A talik depth of 91m was determined from analysis of the transient electromagnetic surveys. Using a lake initiation age of 1400years before present and available subsurface properties the results from thermal modeling of the lake center arrived at a best estimate talk depth of 80m, which is on the same order of magnitude as the results from the transient electromagnetic survey. Our approach has provided a noninvasive estimate of talik geometry suitable for comparable settings throughout circum-Arctic coastal lowland regions.
KW  - geophysics
KW  - permafrost
KW  - thermokarst
KW  - electromagnetic
KW  - lake
Y1  - 2018
U6  - https://doi.org/10.1029/2018JB016121
SN  - 2169-9313
SN  - 2169-9356
VL  - 123
IS  - 11
SP  - 9310
EP  - 9323
PB  - American Geophysical Union
CY  - Washington
ER  - 
TY  - GEN
A1  - Pathe-Neuschäfer-Rube, Andrea
A1  - Neuschäfer-Rube, Frank
A1  - Haas, Gerald
A1  - Langoth-Fehringer, Nina
A1  - Püschel, Gerhard Paul
T1  - Cell-Based Reporter Release Assay to Determine the Potency of Proteolytic Bacterial Neurotoxins
T2  - Toxins
N2  - Despite the implementation of cell-based replacement methods, the mouse lethality assay is still frequently used to determine the activity of botulinum toxin (BoNT) for medical use. One explanation is that due to the use of neoepitope-specific antibodies to detect the cleaved BoNT substrate, the currently devised assays can detect only one specific serotype of the toxin. Recently, we developed a cell-based functional assay, in which BoNT activity is determined by inhibiting the release of a reporter enzyme that is liberated concomitantly with the neurotransmitter from neurosecretory vesicles. In theory, this assay should be suitable to detect the activity of any BoNT serotype. Consistent with this assumption, the current study shows that the stimulus-dependent release of a luciferase from a differentiated human neuroblastoma-based reporter cell line (SIMA-hPOMC1-26-GLuc cells) was inhibited by BoNT-A and-C. Furthermore, this was also inhibited by BoNT-B and tetanus toxin to a lesser extent and at higher concentrations. In order to provide support for the suitability of this technique in practical applications, a dose–response curve obtained with a pharmaceutical preparation of BoNT-A closely mirrored the activity determined in the mouse lethality assay. In summary, the newly established cell-based assay may represent a versatile and specific alternative to the mouse lethality assay and other currently established cell-based assays.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 473 
KW  - botulinum toxin
KW  - BoNT
KW  - tetanus toxin
KW  - RRR
KW  - replacement
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-418141
ER  - 
TY  - JOUR
A1  - Henkel, Janin
A1  - Neuschaefer-Rube, Frank
A1  - Pathe-Neuschaefer-Rube, Andrea
A1  - Püschel, Gerhard Paul
T1  - Aggravation by prostaglandin e-2 of interleukin-6-dependent insulin resistance in hepatocytes
N2  - Hepatic insulin resistance is a major contributor to fasting hyperglycemia in patients with metabolic syndrome and type 2 diabetes. Circumstantial evidence suggests that cyclooxygenase products in addition to cytokines might contribute to insulin resistance. However, direct evidence for a role of prostaglandins in the development of hepatic insulin resistance is lacking. Therefore, the impact of prostaglandin E-2 (PGE(2)) alone and in combination with interleukin-6 (IL-6) on insulin signaling was studied in primary hepatocyte cultures. Rat hepatocytes were incubated with IL-6 and/or PGE(2) and subsequently with insulin. Glycogen synthesis was monitored by radiochemical analysis; the activation state of proteins of the insulin receptor signal chain was analyzed by western blot with phosphospecific antibodies. In hepatocytes, insulin-stimulated glycogen synthesis and insulin-dependent phosphorylation of Akt-kinase were attenuated synergistically by prior incubation with IL-6 and/or PGE(2) while insulin receptor autophosphorylation was barely affected. IL-6 but not PGE(2) induced suppressors of cytokine signaling (SOCS3). PGE(2) but not IL-6 activated extracellular signal-regulated kinase 1/2 (ERK1/2) persistently. Inhibition of ERK1/2 activation by PD98059 abolished the PGE(2)-dependent but not the IL-6-dependent attenuation of insulin signaling. In HepG2 cells expressing a recombinant EP3-receptor, PGE(2) pre-incubation activated ERK1/2, caused a serine phosphorylation of insulin receptor substrate 1 (IRS1), and reduced the insulin-dependent Akt-phosphorylation. Conclusion: PGE(2) might contribute to hepatic insulin resistance via an EP3-receptor-dependent ERK1/2 activation resulting in a serine phosphorylation of insulin receptor substrate, thereby preventing an insulin-dependent activation of Akt and glycogen synthesis. Since different molecular mechanisms appear to be employed, PGE(2) may synergize with IL-6, which interrupted the insulin receptor signal chain, principally by an induction of SOCS, namely SOCS3.
Y1  - 2009
UR  - http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291527-3350
U6  - https://doi.org/10.1002/Hep.23064
SN  - 0270-9139
ER  - 
TY  - JOUR
A1  - Pathe-Neuschaefer-Rube, Andrea
A1  - Neuschaefer-Rube, Frank
A1  - Genz, Lara
A1  - Püschel, Gerhard Paul
T1  - Botulinum Neurotoxin Dose-Dependently Inhibits Release of Neurosecretory Vesicle-Targeted Luciferase from Neuronal Cells
JF  - Alternatives to animal experimentation : ALTEX ; a journal for new paths in biomedical science
N2  - Botulinum toxin is a bacterial toxin that inhibits neurotransmitter release from neurons and thereby causes a flaccid paralysis. It is used as drug to treat a number of serious ailments and, more frequently, for aesthetic medical interventions. Botulinum toxin for pharmacological applications is isolated from bacterial cultures. Due to partial denaturation of the protein, the specific activity of these preparations shows large variations. Because of its extreme potential toxicity, pharmacological preparations must be carefully tested for their activity. For the current gold standard, the mouse lethality assay, several hundred thousand mice are killed per year. Alternative methods have been developed that suffer from one or more of the following deficits: In vitro enzyme assays test only the activity of the catalytic subunit of the toxin. Enzymatic and cell based immunological assays are specific for just one of the different serotypes. The current study takes a completely different approach that overcomes these limitations: Neuronal cell lines were stably transfected with plasmids coding for luciferases of different species, which were N-terminally tagged with leader sequences that redirect the luciferase into neuro-secretory vesicles. From these vesicles, luciferases were released upon depolarization of the cells. The depolarization-dependent release was efficiently inhibited by botulinum toxin in a concentration range (1 to 100 pM) that is used in pharmacological preparations. The new assay might thus be an alternative to the mouse lethality assay and the immunological assays already in use.
KW  - Botulinum toxin
KW  - cell-based assay
KW  - mouse lethality assay
Y1  - 2015
SN  - 1868-596X
SN  - 1868-8551
VL  - 32
IS  - 4
SP  - 297
EP  - 306
PB  - Springer
CY  - Heidelberg
ER  - 
TY  - JOUR
A1  - Pathe-Neuschäfer-Rube, Andrea
A1  - Neuschäfer-Rube, Frank
A1  - Haas, Gerald
A1  - Langoth-Fehringer, Nina
A1  - Püschel, Gerhard Paul
T1  - Cell-Based Reporter Release Assay to Determine the Potency of Proteolytic Bacterial Neurotoxins
JF  - Toxins
N2  - Despite the implementation of cell-based replacement methods, the mouse lethality assay is still frequently used to determine the activity of botulinum toxin (BoNT) for medical use. One explanation is that due to the use of neoepitope-specific antibodies to detect the cleaved BoNT substrate, the currently devised assays can detect only one specific serotype of the toxin. Recently, we developed a cell-based functional assay, in which BoNT activity is determined by inhibiting the release of a reporter enzyme that is liberated concomitantly with the neurotransmitter from neurosecretory vesicles. In theory, this assay should be suitable to detect the activity of any BoNT serotype. Consistent with this assumption, the current study shows that the stimulus-dependent release of a luciferase from a differentiated human neuroblastoma-based reporter cell line (SIMA-hPOMC1-26-GLuc cells) was inhibited by BoNT-A and-C. Furthermore, this was also inhibited by BoNT-B and tetanus toxin to a lesser extent and at higher concentrations. In order to provide support for the suitability of this technique in practical applications, a dose–response curve obtained with a pharmaceutical preparation of BoNT-A closely mirrored the activity determined in the mouse lethality assay. In summary, the newly established cell-based assay may represent a versatile and specific alternative to the mouse lethality assay and other currently established cell-based assays.
KW  - botulinum toxin
KW  - BoNT
KW  - tetanus toxin
KW  - RRR
KW  - replacement
Y1  - 2018
U6  - https://doi.org/10.3390/toxins10090360
SN  - 2072-6651
VL  - 10
IS  - 9
SP  - 1
EP  - 10
PB  - Molecular Diversity Preservation International (MDPI)
CY  - Basel
ER  - 
TY  - JOUR
A1  - Pathe-Neuschäfer-Rube, Andrea
A1  - Neuschäfer-Rube, Frank
A1  - Püschel, Gerhard Paul
T1  - Role of the ERC motif in the proximal part of the second intracellular loop and the C-terminal domain of the human prostaglandin F2alpha receptor (hFP-R) in G-protein coupling control
N2  - The human FP-R (F2alpha prostaglandin receptor) is a Gq-coupled heptahelical ectoreceptor, which is of significant medical interest, since it is a potential target for the treatment of glaucoma and preterm labour. On agonist exposure, it mediates an increase in intracellular inositol phosphate formation. Little is known about the structures that govern the agonist-dependent receptor activation. In other prostanoid receptors, the C-terminal domain has been inferred in the control of agonist-dependent receptor activation. A DRY motif at the beginning of the second intracellular loop is highly conserved throughout the G-protein-coupled receptor family and appears to be crucial for controlling agonist-dependent receptor activation. It is replaced by an ERC motif in the FP-R and no evidence for the relevance of this motif in ligand-dependent activation of prostanoid receptors has been provided so far. The aim of the present study was to elucidate the potential role of the C-terminal domain and the ERC motif in agonist-controlled intracellular signalling in FP-R mutants generated by site-directed mutagenesis. It was found that substitution of the acidic Glu(132) in the ERC motif by a threonine residue led to full constitutive activation, whereas truncation of the receptor's C-terminal domain led to partial constitutive activation of all three intracellular signal pathways that had previously been shown to be activated by the FP-R, i.e. inositol trisphosphate formation, focal adhesion kinase activation and T-cell factor signalling. Inositol trisphosphate formation and focal adhesion kinase phosphorylation were further enhanced by ligand binding in cells expressing the truncation mutant but not the E132T (Glu132-->Thr) mutant. Thus C-terminal truncation appeared to result in a receptor with partial constitutive activation, whereas substitution of Glu132 by threonine apparently resulted in a receptor with full constitutive activity.
Y1  - 2005
UR  - http://www.biochemj.org/bj/388/0317/bj3880317.htm
ER  - 
TY  - JOUR
A1  - Neuschäfer-Rube, Frank
A1  - Hermosilla, Ricardo
A1  - Kuna, Manuela
A1  - Pathe-Neuschäfer-Rube, Andrea
A1  - Schulein, R.
A1  - Püschel, Gerhard Paul
T1  - A Ser/Thr cluster within the C-terminal domain of the rat prostaglandin receptor EP3 alpha is essential for agonist-induced phosphorylation, desensitization and internalization
N2  - 1 Two isoforms of the rat prostaglandin E-2 receptor, rEP3 alpha-R and rEP3 beta-R, differ only in their C- terminal domain. To analyze the function of the rEP3-R C-terminal domain in agonist induced desensitization, a cluster of Ser/Thr residues in the C-terminal domain of the rEP3 alpha-R was mutated to Ala and both isoforms and the receptor mutant (rEP3 alpha-ST341-349A-R) were stably expressed in HEK293 cells. 2 All rEP3-R receptors showed a similar ligand- binding profile. They were functionally coupled to Gi and reduced forskolin-induced cAMP-formation. 3 Repeated exposure of cells expressing the rEP3 alpha-R isoform to PGE(2) reduced the agonist induced inhibition of forskolin-stimulated cAMP-formation by 50% and led to internalization of the receptor to intracellular endocytotic vesicles. By contrast, Gi- response as well as plasma membrane localization of the rEP3 beta-R and the rEP3 alpha-ST341-349A-R were not affected by prior agonist-stimulation. 4 Agonist-stimulation of HEK293-rEP3 alpha-R cells induced a time- and dose-dependent phosphorylation of the receptor most likely by G protein-coupled receptor kinases and not by protein kinase A or protein kinase C. By contrast, upon agonist-stimulation the rEP3 beta-R was not phosphorylated and the rEP3 alpha-ST341-349A-R was phosphorylated only weakly. 5 These results led to the hypothesis that agonist-induced desensitization of the rEP3 alpha-R isoform is mediated most likely by a GRK-dependent phosphorylation of Ser/Thr residues 341 - 349. Phosphorylation then initiates uncoupling of the receptor from Gi protein and receptor internalization
Y1  - 2005
SN  - 0007-1188
ER  -