TY - JOUR A1 - Hoppe, J. A1 - Gatti, D. A1 - Weber, H. A1 - Sebald, Walter T1 - Labeling of individual amino acid residues in the membrane-embedded F\(_0\) part of the F\(_1\) F\(_0\) ATP synthase from Neurospora crassa. Influence of oligomycin and dicyclohexylcarbodiimide N2 - Three F0 subunits and the F\(_1\) subunit P of the ATP synthase from Neurospora crassa were labeled with the lipophilic photoactivatable reagent 3-(trifluoromethyl)-3-(m-[\(^{125}\)I]iodophenyl)diazirine ([\(^{125}\)I]TID). In the proteolipid subunit which was the most heavily labeled polypeptide labeling was confmed to five residues at the NH2-terminus and five residues at the C-terminus ofthe protein. Labeling occurred at similar positions compared with the homologaus protein (subunit c) in the ATP synthase from Escherichia coli, indicating a similar structure of the proteolipid subunits in their respective organisms. The inhibitors oligomycin and dicyclohexylcarbodiimide did not change the pattern of accessible surface residues in the proteolipid, suggesting that neither inhibitor induces gross conformational changes. However, in the presence of oligomycin, the extent oflabeling in some residues was reduced. Apparently, these residues provide part of the binding site for the inhibitor. After reaction with dicyclohexylcarbodiimide an additional labeled amino acid was found at position 65 corresponding to the invariant carbodümide-binding glutamic acid. These results and previous observations indicate that the carboxyl side chain of Glu-65 is located at the protein-lipid interphase. The idea is discussed that proton translocation occurs at the interphase between different types if F\(_0\) subunits. Dicyclohexylcarbodiimide or oligomycin might disturb this essential interaction between the F\(_0\) subunits. KW - Biochemie Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62598 ER - TY - JOUR A1 - Straube, B. A1 - Reif, A. A1 - Richter, J. A1 - Lueken, U. A1 - Weber, H. A1 - Arolt, V. A1 - Jansen, A. A1 - Zwanzger, P. A1 - Domschke, K. A1 - Pauli, P. A1 - Konrad, C. A1 - Gerlach, A. L. A1 - Lang, T. A1 - Fydrich, T. A1 - Alpers, G. W. A1 - Stroehle, A. A1 - Wittmann, A. A1 - Pfleiderer, B. A1 - Wittchen, H.-U. A1 - Hamm, A. A1 - Deckert, J. A1 - Kircher, T. T1 - The functional - 1019C/G HTR1A polymorphism and mechanisms of fear JF - Translational Psychiatry N2 - Serotonin receptor 1A gene (HTR1A) knockout mice show pronounced defensive behaviour and increased fear conditioning to ambiguous conditioned stimuli. Such behaviour is a hallmark of pathological human anxiety, as observed in panic disorder with agoraphobia (PD/AG). Thus, variations in HTR1A might contribute to neurophysiological differences within subgroups of PD/AG patients. Here, we tested this hypothesis by combining genetic with behavioural techniques and neuroimaging. In a clinical multicentre trial, patients with PD/AG received 12 sessions of manualized cognitive-behavioural therapy (CBT) and were genotyped for HTR1A rs6295. In four subsamples of this multicentre trial, exposure behaviour (n = 185), defensive reactivity measured using a behavioural avoidance test (BAT; before CBT: n = 245; after CBT: n = 171) and functional magnetic resonance imaging (fMRI) data during fear conditioning were acquired before and after CBT (n = 39). HTR1A risk genotype (GG) carriers more often escaped during the BAT before treatment. Exploratory fMRI results suggest increased activation of the amygdala in response to threat as well as safety cues before and after treatment in GG carriers. Furthermore, GG carriers demonstrated reduced effects of CBT on differential conditioning in regions including the bilateral insulae and the anterior cingulate cortex. Finally, risk genotype carriers demonstrated reduced self-initiated exposure behaviour to aversive situations. This study demonstrates the effect of HTR1A variation on defensive behaviour, amygdala activity, CBT-induced neural plasticity and normalization of defence behaviour in PD/AG. Our results, therefore, translate evidence from animal studies to humans and suggest a central role for HTR1A in differentiating subgroups of patients with anxiety disorders. KW - randomized-controlled trial KW - panic disorder KW - 5-HT1A receptor KW - defensive reactivity KW - major depression KW - cognitive-behavioral therapy KW - receptor gene polymorphism KW - C(-1019)G polymorphism KW - anxiety disorders KW - serotonin(1A) receptor Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-114369 SN - 2158-3188 VL - 4 ER - TY - JOUR A1 - Lueken, U A1 - Kuhn, M A1 - Yang, Y A1 - Straube, B A1 - Kircher, T A1 - Wittchen, H-U A1 - Pfleiderer, B A1 - Arolt, V A1 - Wittmann, A A1 - Ströhle, A A1 - Weber, H A1 - Reif, A A1 - Domschke, K A1 - Deckert, J A1 - Lonsdorf, TB T1 - Modulation of defensive reactivity by GLRB allelic variation: converging evidence from an intermediate phenotype approach JF - Translational Psychiatry N2 - Representing a phylogenetically old and very basic mechanism of inhibitory neurotransmission, glycine receptors have been implicated in the modulation of behavioral components underlying defensive responding toward threat. As one of the first findings being confirmed by genome-wide association studies for the phenotype of panic disorder and agoraphobia, allelic variation in a gene coding for the glycine receptor beta subunit (GLRB) has recently been associated with increased neural fear network activation and enhanced acoustic startle reflexes. On the basis of two independent healthy control samples, we here aimed to further explore the functional significance of the GLRB genotype (rs7688285) by employing an intermediate phenotype approach. We focused on the phenotype of defensive system reactivity across the levels of brain function, structure, and physiology. Converging evidence across both samples was found for increased neurofunctional activation in the (anterior) insular cortex in GLRB risk allele carriers and altered fear conditioning as a function of genotype. The robustness of GLRB effects is demonstrated by consistent findings across different experimental fear conditioning paradigms and recording sites. Altogether, findings provide translational evidence for glycine neurotransmission as a modulator of the brain’s evolutionary old dynamic defensive system and provide further support for a strong, biologically plausible candidate intermediate phenotype of defensive reactivity. As such, glycine-dependent neurotransmission may open up new avenues for mechanistic research on the etiopathogenesis of fear and anxiety disorders. KW - glycine receptor beta subunit KW - neural fear network activation KW - intermediate phenotype approach KW - defensive system reactivity Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-182381 VL - 7 IS - e1227 ER -