TY  - JOUR
A1  - Lohse, Christian
A1  - Bock, Andreas
A1  - Maiellaro, Isabella
A1  - Hannawacker, Annette
A1  - Schad, Lothar R.
A1  - Lohse, Martin J.
A1  - Bauer, Wolfgang R.
T1  - Experimental and mathematical analysis of cAMP nanodomains
JF  - PLoS ONE
N2  - In their role as second messengers, cyclic nucleotides such as cAMP have a variety of intracellular effects. These complex tasks demand a highly organized orchestration of spatially and temporally confined cAMP action which should be best achieved by compartmentalization of the latter. A great body of evidence suggests that cAMP compartments may be established and maintained by cAMP degrading enzymes, e.g. phosphodiesterases (PDEs). However, the molecular and biophysical details of how PDEs can orchestrate cAMP gradients are entirely unclear. In this paper, using fusion proteins of cAMP FRET-sensors and PDEs in living cells, we provide direct experimental evidence that the cAMP concentration in the vicinity of an individual PDE molecule is below the detection limit of our FRET sensors (<100nM). This cAMP gradient persists in crude cytosol preparations. We developed mathematical models based on diffusion-reaction equations which describe the creation of nanocompartments around a single PDE molecule and more complex spatial PDE arrangements. The analytically solvable equations derived here explicitly determine how the capability of a single PDE, or PDE complexes, to create a nanocompartment depend on the cAMP degradation rate, the diffusive mobility of cAMP, and geometrical and topological parameters. We apply these generic models to our experimental data and determine the diffusive mobility and degradation rate of cAMP. The results obtained for these parameters differ by far from data in literature for free soluble cAMP interacting with PDE. Hence, restricted cAMP diffusion in the vincinity of PDE is necessary to create cAMP nanocompartments in cells.
KW  - fluorescence resonance energy transfer
KW  - yellow fluorescent protein
KW  - radii
KW  - adenylyl cyclase signaling cascade
KW  - cell fusion
KW  - cytosol
KW  - isoproterenol
KW  - absorption
KW  - cyclic nucleotides such as cyclic adenosine monophosphate
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170972
VL  - 12
IS  - 4
ER  - 
TY  - JOUR
A1  - Schönegge, Anne-Marie
A1  - Gallion, Jonathan
A1  - Picard, Louis-Philippe
A1  - Wilkins, Angela D.
A1  - Le Gouill, Christian
A1  - Audet, Martin
A1  - Stallaert, Wayne
A1  - Lohse, Martin J.
A1  - Kimmel, Marek
A1  - Lichtarge, Olivier
A1  - Bouvier, Michel
T1  - Evolutionary action and structural basis of the allosteric switch controlling β\(_2\)AR functional selectivity
JF  - Nature Communications
N2  - Functional selectivity of G-protein-coupled receptors is believed to originate from ligand-specific conformations that activate only subsets of signaling effectors. In this study, to identify molecular motifs playing important roles in transducing ligand binding into distinct signaling responses, we combined in silico evolutionary lineage analysis and structure-guided site-directed mutagenesis with large-scale functional signaling characterization and non-negative matrix factorization clustering of signaling profiles. Clustering based on the signaling profiles of 28 variants of the β\(_2\)-adrenergic receptor reveals three clearly distinct phenotypical clusters, showing selective impairments of either the Gi or βarrestin/endocytosis pathways with no effect on Gs activation. Robustness of the results is confirmed using simulation-based error propagation. The structural changes resulting from functionally biasing mutations centered around the DRY, NPxxY, and PIF motifs, selectively linking these micro-switches to unique signaling profiles. Our data identify different receptor regions that are important for the stabilization of distinct conformations underlying functional selectivity.
KW  - toxicology
KW  - functional clustering
KW  - molecular modelling
KW  - protein design
KW  - receptor pharmacology
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172268
VL  - 8
ER  - 
TY  - JOUR
A1  - Sadovnick, A. Dessa
A1  - Traboulsee, Anthony L.
A1  - Bernales, Cecily Q.
A1  - Ross, Jay P.
A1  - Forwell, Amanda L.
A1  - Yee, Irene M.
A1  - Guillot-Noel, Lena
A1  - Fontaine, Bertrand
A1  - Cournu-Rebeix, Isabelle
A1  - Alcina, Antonio
A1  - Fedetz, Maria
A1  - Izquierdo, Guillermo
A1  - Matesanz, Fuencisla
A1  - Hilven, Kelly
A1  - Dubois, Bénédicte
A1  - Goris, An
A1  - Astobiza, Ianire
A1  - Alloza, Iraide
A1  - Antigüedad, Alfredo
A1  - Vandenbroeck, Koen
A1  - Akkad, Denis A.
A1  - Aktas, Orhan
A1  - Blaschke, Paul
A1  - Buttmann, Mathias
A1  - Chan, Andrew
A1  - Epplen, Joerg T.
A1  - Gerdes, Lisa-Ann
A1  - Kroner, Antje
A1  - Kubisch, Christian
A1  - Kümpfel, Tania
A1  - Lohse, Peter
A1  - Rieckmann, Peter
A1  - Zettl, Uwe K.
A1  - Zipp, Frauke
A1  - Bertram, Lars
A1  - Lill, Christina M.
A1  - Fernandez, Oscar
A1  - Urbaneja, Patricia
A1  - Leyva, Laura
A1  - Alvarez-Cermeño, Jose Carlos
A1  - Arroyo, Rafael
A1  - Garagorri, Aroa M.
A1  - García-Martínez, Angel
A1  - Villar, Luisa M.
A1  - Urcelay, Elena
A1  - Malhotra, Sunny
A1  - Montalban, Xavier
A1  - Comabella, Manuel
A1  - Berger, Thomas
A1  - Fazekas, Franz
A1  - Reindl, Markus
A1  - Schmied, Mascha C.
A1  - Zimprich, Alexander
A1  - Vilariño-Güell, Carles
T1  - Analysis of Plasminogen Genetic Variants in Multiple Sclerosis Patients
JF  - G3: Genes Genomes Genetics
N2  - Multiple sclerosis (MS) is a prevalent neurological disease of complex etiology. Here, we describe the characterization of a multi-incident MS family that nominated a rare missense variant (p.G420D) in plasminogen (PLG) as a putative genetic risk factor for MS. Genotyping of PLG p.G420D (rs139071351) in 2160 MS patients, and 886 controls from Canada, identified 10 additional probands, two sporadic patients and one control with the variant. Segregation in families harboring the rs139071351 variant, identified p.G420D in 26 out of 30 family members diagnosed with MS, 14 unaffected parents, and 12 out of 30 family members not diagnosed with disease. Despite considerably reduced penetrance, linkage analysis supports cosegregation of PLG p.G420D and disease. Genotyping of PLG p.G420D in 14446 patients, and 8797 controls from Canada, France, Spain, Germany, Belgium, and Austria failed to identify significant association with disease (P = 0.117), despite an overall higher prevalence in patients (OR = 1.32; 95% CI = 0.93–1.87). To assess whether additional rare variants have an effect on MS risk, we sequenced PLG in 293 probands, and genotyped all rare variants in cases and controls. This analysis identified nine rare missense variants, and although three of them were exclusively observed in MS patients, segregation does not support pathogenicity. PLG is a plausible biological candidate for MS owing to its involvement in immune system response, blood-brain barrier permeability, and myelin degradation. Moreover, components of its activation cascade have been shown to present increased activity or expression in MS patients compared to controls; further studies are needed to clarify whether PLG is involved in MS susceptibility.
KW  - multiple sclerosis
KW  - genetics
KW  - linkage
KW  - association
KW  - plasminogen
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165405
VL  - 6
IS  - 7
ER  -