--- _id: '7525' abstract: - lang: eng text: "The medial habenula (MHb) is an evolutionary conserved epithalamic structure important for the modulation of emotional memory. It is involved in regulation of anxiety, compulsive behavior, addiction (nicotinic and opioid), sexual and feeding behavior. MHb receives inputs from septal regions and projects exclusively to the interpeduncular nucleus (IPN). Distinct sub-regions of the septum project to different subnuclei of MHb: the bed nucleus of anterior commissure projects to dorsal MHb and the triangular septum projects to ventral MHb. Furthermore, the dorsal and ventral MHb project to the lateral and rostral/central IPN, respectively. Importantly, these projections have unique features of prominent co-release of different neurotransmitters and requirement of a peculiar type of calcium channel for release. In general, synaptic neurotransmission requires an activity-dependent influx of Ca2+ into the presynaptic terminal through voltage-gated calcium channels. The calcium channel family most commonly involved in neurotransmitter release comprises three members, P/Q-, N- and R-type with Cav2.1, Cav2.2 and Cav2.3 subunits, respectively. In contrast to most CNS synapses that mainly express Cav2.1 and/or Cav2.2, MHb terminals in the IPN exclusively express Cav2.3. In other parts of the brain, such as the hippocampus, Cav2.3 is mostly located to postsynaptic elements. This unusual presynaptic location of Cav2.3 in the MHb-IPN pathway implies unique mechanisms of glutamate release in this pathway. One potential example of such uniqueness is the facilitation of release by GABAB receptor (GBR) activation. Presynaptic GBRs usually inhibit the release of neurotransmitters by inhibiting presynaptic calcium channels. MHb shows the highest expression levels of GBR in the brain. GBRs comprise two subunits, GABAB1 (GB1) and GABAB2 (GB2), and are associated with auxiliary subunits, called potassium channel tetramerization domain containing proteins (KCTD) 8, 12, 12b and 16. Among these four subunits, KCTD12b is exclusively expressed in ventral MHb, and KCTD8 shows the strongest expression in the whole MHb among other brain regions, indicating that KCTD8 and KCTD12b may be involved in the unique mechanisms of neurotransmitter release mediated by Cav2.3 and regulated by GBRs in this pathway. \r\nIn the present study, we first verified that neurotransmission in both dorsal and ventral MHb-IPN pathways is mainly mediated by Cav2.3 using a selective blocker of R-type channels, SNX-482. We next found that baclofen, a GBR agonist, has facilitatory effects on release from ventral MHb terminal in rostral IPN, whereas it has inhibitory effects on release from dorsal MHb terminals in lateral IPN, indicating that KCTD12b expressed exclusively in ventral MHb may have a role in the facilitatory effects of GBR activation. In a heterologous expression system using HEK cells, we found that KCTD8 and KCTD12b but not KCTD12 directly bind with Cav2.3. Pre-embedding immunogold electron microscopy data show that Cav2.3 and KCTD12b are distributed most densely in presynaptic active zone in IPN with KCTD12b being present only in rostral/central but not lateral IPN, whereas GABAB, KCTD8 and KCTD12 are distributed most densely in perisynaptic sites with KCTD12 present more frequently in postsynaptic elements and only in rostral/central IPN. In freeze-fracture replica labelling, Cav2.3, KCTD8 and KCTD12b are co-localized with each other in the same active zone indicating that they may form complexes regulating vesicle release in rostral IPN. \r\nOn electrophysiological studies of wild type (WT) mice, we found that paired-pulse ratio in rostral IPN of KCTD12b knock-out (KO) mice is lower than those of WT and KCTD8 KO mice. Consistent with this finding, in mean variance analysis, release probability in rostral IPN of KCTD12b KO mice is higher than that of WT and KCTD8 KO mice. Although paired-pulse ratios are not different between WT and KCTD8 KO mice, the mean variance analysis revealed significantly lower release probability in rostral IPN of KCTD8 KO than WT mice. These results demonstrate bidirectional regulation of Cav2.3-mediated release by KCTD8 and KCTD12b without GBR activation in rostral IPN. Finally, we examined the baclofen effects in rostral IPN of KCTD8 and KCTD12b KO mice, and found the facilitation of release remained in both KO mice, indicating that the peculiar effects of the GBR activation in this pathway do not depend on the selective expression of these KCTD subunits in ventral MHb. However, we found that presynaptic potentiation of evoked EPSC amplitude by baclofen falls to baseline after washout faster in KCTD12b KO mice than WT, KCTD8 KO and KCTD8/12b double KO mice. This result indicates that KCTD12b is involved in sustained potentiation of vesicle release by GBR activation, whereas KCTD8 is involved in its termination in the absence of KCTD12b. Consistent with these functional findings, replica labelling revealed an increase in density of KCTD8, but not Cav2.3 or GBR at active zone in rostral IPN of KCTD12b KO mice compared with that of WT mice, suggesting that increased association of KCTD8 with Cav2.3 facilitates the release probability and termination of the GBR effect in the absence of KCTD12b.\r\nIn summary, our study provided new insights into the physiological roles of presynaptic Cav2.3, GBRs and their auxiliary subunits KCTDs at an evolutionary conserved neuronal circuit. Future studies will be required to identify the exact molecular mechanism underlying the GBR-mediated presynaptic potentiation on ventral MHb terminals. It remains to be determined whether the prominent presence of presynaptic KCTDs at active zone could exert similar neuromodulatory functions in different pathways of the brain.\r\n" acknowledged_ssus: - _id: EM-Fac alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Pradeep full_name: Bhandari, Pradeep id: 45EDD1BC-F248-11E8-B48F-1D18A9856A87 last_name: Bhandari orcid: 0000-0003-0863-4481 citation: ama: Bhandari P. Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway. 2020. doi:10.15479/AT:ISTA:7525 apa: Bhandari, P. (2020). Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:7525 chicago: Bhandari, Pradeep. “Localization and Functional Role of Cav2.3 in the Medial Habenula to Interpeduncular Nucleus Pathway.” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:7525. ieee: P. Bhandari, “Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway,” Institute of Science and Technology Austria, 2020. ista: Bhandari P. 2020. Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway. Institute of Science and Technology Austria. mla: Bhandari, Pradeep. Localization and Functional Role of Cav2.3 in the Medial Habenula to Interpeduncular Nucleus Pathway. Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:7525. short: P. Bhandari, Localization and Functional Role of Cav2.3 in the Medial Habenula to Interpeduncular Nucleus Pathway, Institute of Science and Technology Austria, 2020. date_created: 2020-02-26T10:56:37Z date_published: 2020-02-28T00:00:00Z date_updated: 2023-09-07T13:20:03Z day: '28' ddc: - '570' degree_awarded: PhD department: - _id: RySh doi: 10.15479/AT:ISTA:7525 file: - access_level: open_access checksum: 4589234fdb12b4ad72273b311723a7b4 content_type: application/pdf creator: pbhandari date_created: 2020-02-28T08:37:53Z date_updated: 2021-03-01T23:30:04Z embargo: 2021-02-28 file_id: '7538' file_name: Pradeep Bhandari Thesis.pdf file_size: 9646346 relation: main_file title: Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway - access_level: closed checksum: aa79490553ca0a5c9b6fbcd152e93928 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: pbhandari date_created: 2020-02-28T08:47:14Z date_updated: 2021-03-01T23:30:04Z embargo_to: open_access file_id: '7539' file_name: Pradeep Bhandari Thesis.docx file_size: 35252164 relation: source_file title: Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway file_date_updated: 2021-03-01T23:30:04Z has_accepted_license: '1' keyword: - Cav2.3 - medial habenula (MHb) - interpeduncular nucleus (IPN) language: - iso: eng month: '02' oa: 1 oa_version: Published Version page: '79' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Ryuichi full_name: Shigemoto, Ryuichi id: 499F3ABC-F248-11E8-B48F-1D18A9856A87 last_name: Shigemoto orcid: 0000-0001-8761-9444 title: Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2020' ... --- _id: '8657' abstract: - lang: eng text: "Synthesis of proteins – translation – is a fundamental process of life. Quantitative studies anchor translation into the context of bacterial physiology and reveal several mathematical relationships, called “growth laws,” which capture physiological feedbacks between protein synthesis and cell growth. Growth laws describe the dependency of the ribosome abundance as a function of growth rate, which can change depending on the growth conditions. Perturbations of translation reveal that bacteria employ a compensatory strategy in which the reduced translation capability results in increased expression of the translation machinery.\r\nPerturbations of translation are achieved in various ways; clinically interesting is the application of translation-targeting antibiotics – translation inhibitors. The antibiotic effects on bacterial physiology are often poorly understood. Bacterial responses to two or more simultaneously applied antibiotics are even more puzzling. The combined antibiotic effect determines the type of drug interaction, which ranges from synergy (the effect is stronger than expected) to antagonism (the effect is weaker) and suppression (one of the drugs loses its potency).\r\nIn the first part of this work, we systematically measure the pairwise interaction network for translation inhibitors that interfere with different steps in translation. We find that the interactions are surprisingly diverse and tend to be more antagonistic. To explore the underlying mechanisms, we begin with a minimal biophysical model of combined antibiotic action. We base this model on the kinetics of antibiotic uptake and binding together with the physiological response described by the growth laws. The biophysical model explains some drug interactions, but not all; it specifically fails to predict suppression.\r\nIn the second part of this work, we hypothesize that elusive suppressive drug interactions result from the interplay between ribosomes halted in different stages of translation. To elucidate this putative mechanism of drug interactions between translation inhibitors, we generate translation bottlenecks genetically using in- ducible control of translation factors that regulate well-defined translation cycle steps. These perturbations accurately mimic antibiotic action and drug interactions, supporting that the interplay of different translation bottlenecks partially causes these interactions.\r\nWe extend this approach by varying two translation bottlenecks simultaneously. This approach reveals the suppression of translocation inhibition by inhibited translation. We rationalize this effect by modeling dense traffic of ribosomes that move on transcripts in a translation factor-mediated manner. This model predicts a dissolution of traffic jams caused by inhibited translocation when the density of ribosome traffic is reduced by lowered initiation. We base this model on the growth laws and quantitative relationships between different translation and growth parameters.\r\nIn the final part of this work, we describe a set of tools aimed at quantification of physiological and translation parameters. We further develop a simple model that directly connects the abundance of a translation factor with the growth rate, which allows us to extract physiological parameters describing initiation. We demonstrate the development of tools for measuring translation rate.\r\nThis thesis showcases how a combination of high-throughput growth rate mea- surements, genetics, and modeling can reveal mechanisms of drug interactions. Furthermore, by a gradual transition from combinations of antibiotics to precise genetic interventions, we demonstrated the equivalency between genetic and chemi- cal perturbations of translation. These findings tile the path for quantitative studies of antibiotic combinations and illustrate future approaches towards the quantitative description of translation." acknowledged_ssus: - _id: LifeSc - _id: M-Shop acknowledgement: I thank Life Science Facilities for their continuous support with providing top-notch laboratory materials, keeping the devices humming, and coordinating the repairs and building of custom-designed laboratory equipment with the MIBA Machine shop. alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Bor full_name: Kavcic, Bor id: 350F91D2-F248-11E8-B48F-1D18A9856A87 last_name: Kavcic orcid: 0000-0001-6041-254X citation: ama: 'Kavcic B. Perturbations of protein synthesis: from antibiotics to genetics and physiology. 2020. doi:10.15479/AT:ISTA:8657' apa: 'Kavcic, B. (2020). Perturbations of protein synthesis: from antibiotics to genetics and physiology. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:8657' chicago: 'Kavcic, Bor. “Perturbations of Protein Synthesis: From Antibiotics to Genetics and Physiology.” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:8657.' ieee: 'B. Kavcic, “Perturbations of protein synthesis: from antibiotics to genetics and physiology,” Institute of Science and Technology Austria, 2020.' ista: 'Kavcic B. 2020. Perturbations of protein synthesis: from antibiotics to genetics and physiology. Institute of Science and Technology Austria.' mla: 'Kavcic, Bor. Perturbations of Protein Synthesis: From Antibiotics to Genetics and Physiology. Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:8657.' short: 'B. Kavcic, Perturbations of Protein Synthesis: From Antibiotics to Genetics and Physiology, Institute of Science and Technology Austria, 2020.' date_created: 2020-10-13T16:46:14Z date_published: 2020-10-14T00:00:00Z date_updated: 2023-09-07T13:20:48Z day: '14' ddc: - '571' - '530' - '570' degree_awarded: PhD department: - _id: GaTk doi: 10.15479/AT:ISTA:8657 file: - access_level: open_access checksum: d708ecd62b6fcc3bc1feb483b8dbe9eb content_type: application/pdf creator: bkavcic date_created: 2020-10-15T06:41:20Z date_updated: 2021-10-07T22:30:03Z embargo: 2021-10-06 file_id: '8663' file_name: kavcicB_thesis202009.pdf file_size: 52636162 relation: main_file - access_level: closed checksum: bb35f2352a04db19164da609f00501f3 content_type: application/zip creator: bkavcic date_created: 2020-10-15T06:41:53Z date_updated: 2021-10-07T22:30:03Z embargo_to: open_access file_id: '8664' file_name: 2020b.zip file_size: 321681247 relation: source_file file_date_updated: 2021-10-07T22:30:03Z has_accepted_license: '1' language: - iso: eng month: '10' oa: 1 oa_version: Published Version page: '271' publication_identifier: isbn: - 978-3-99078-011-4 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '7673' relation: part_of_dissertation status: public - id: '8250' relation: part_of_dissertation status: public status: public supervisor: - first_name: Gašper full_name: Tkačik, Gašper id: 3D494DCA-F248-11E8-B48F-1D18A9856A87 last_name: Tkačik orcid: 0000-0002-6699-1455 - first_name: Mark Tobias full_name: Bollenbach, Mark Tobias id: 3E6DB97A-F248-11E8-B48F-1D18A9856A87 last_name: Bollenbach orcid: 0000-0003-4398-476X title: 'Perturbations of protein synthesis: from antibiotics to genetics and physiology' type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2020' ... --- _id: '7680' abstract: - lang: eng text: "Proteins and their complex dynamic interactions regulate cellular mechanisms from sensing and transducing extracellular signals, to mediating genetic responses, and sustaining or changing cell morphology. To manipulate these protein-protein interactions (PPIs) that govern the behavior and fate of cells, synthetically constructed, genetically encoded tools provide the means to precisely target proteins of interest (POIs), and control their subcellular localization and activity in vitro and in vivo. Ideal synthetic tools react to an orthogonal cue, i.e. a trigger that does not activate any other endogenous process, thereby allowing manipulation of the POI alone.\r\nIn optogenetics, naturally occurring photosensory domain from plants, algae and bacteria are re-purposed and genetically fused to POIs. Illumination with light of a specific wavelength triggers a conformational change that can mediate PPIs, such as dimerization or oligomerization. By using light as a trigger, these tools can be activated with high spatial and temporal precision, on subcellular and millisecond scales. Chemogenetic tools consist of protein domains that recognize and bind small molecules. By genetic fusion to POIs, these domains can mediate PPIs upon addition of their specific ligands, which are often synthetically designed to provide highly specific interactions and exhibit good bioavailability.\r\nMost optogenetic tools to mediate PPIs are based on well-studied photoreceptors responding to red, blue or near-UV light, leaving a striking gap in the green band of the visible light spectrum. Among both optogenetic and chemogenetic tools, there is an abundance of methods to induce PPIs, but tools to disrupt them require UV illumination, rely on covalent linkage and subsequent enzymatic cleavage or initially result in protein clustering of unknown stoichiometry.\r\nThis work describes how the recently structurally and photochemically characterized green-light responsive cobalamin-binding domains (CBDs) from bacterial transcription factors were re-purposed to function as a green-light responsive optogenetic tool. In contrast to previously engineered optogenetic tools, CBDs do not induce PPI, but rather confer a PPI already upon expression, which can be rapidly disrupted by illumination. This was employed to mimic inhibition of constitutive activity of a growth factor receptor, and successfully implement for cell signalling in mammalian cells and in vivo to rescue development in zebrafish. This work further describes the development and application of a chemically induced de-dimerizer (CDD) based on a recently identified and structurally described bacterial oxyreductase. CDD forms a dimer upon expression in absence of its cofactor, the flavin derivative F420. Safety and of domain expression and ligand exposure are demonstrated in vitro and in vivo in zebrafish. The system is further applied to inhibit cell signalling output from a chimeric receptor upon F420 treatment.\r\nCBDs and CDD expand the repertoire of synthetic tools by providing novel mechanisms of mediating PPIs, and by recognizing previously not utilized cues. In the future, they can readily be combined with existing synthetic tools to functionally manipulate PPIs in vitro and in vivo." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Stephanie full_name: Kainrath, Stephanie id: 32CFBA64-F248-11E8-B48F-1D18A9856A87 last_name: Kainrath citation: ama: Kainrath S. Synthetic tools for optogenetic and chemogenetic inhibition of cellular signals. 2020. doi:10.15479/AT:ISTA:7680 apa: Kainrath, S. (2020). Synthetic tools for optogenetic and chemogenetic inhibition of cellular signals. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:7680 chicago: Kainrath, Stephanie. “Synthetic Tools for Optogenetic and Chemogenetic Inhibition of Cellular Signals.” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:7680. ieee: S. Kainrath, “Synthetic tools for optogenetic and chemogenetic inhibition of cellular signals,” Institute of Science and Technology Austria, 2020. ista: Kainrath S. 2020. Synthetic tools for optogenetic and chemogenetic inhibition of cellular signals. Institute of Science and Technology Austria. mla: Kainrath, Stephanie. Synthetic Tools for Optogenetic and Chemogenetic Inhibition of Cellular Signals. Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:7680. short: S. Kainrath, Synthetic Tools for Optogenetic and Chemogenetic Inhibition of Cellular Signals, Institute of Science and Technology Austria, 2020. date_created: 2020-04-24T16:00:51Z date_published: 2020-04-24T00:00:00Z date_updated: 2023-09-22T09:20:10Z day: '24' ddc: - '570' degree_awarded: PhD department: - _id: CaGu doi: 10.15479/AT:ISTA:7680 file: - access_level: open_access checksum: fb9a4468eb27be92690728e35c823796 content_type: application/pdf creator: stgingl date_created: 2020-04-28T11:19:21Z date_updated: 2021-10-31T23:30:05Z embargo: 2021-10-30 file_id: '7692' file_name: Thesis_without-signatures_PDFA.pdf file_size: 3268017 relation: main_file - access_level: closed checksum: f6c80ca97104a631a328cb79a2c53493 content_type: application/octet-stream creator: stgingl date_created: 2020-04-28T11:19:24Z date_updated: 2021-10-31T23:30:05Z embargo_to: open_access file_id: '7693' file_name: Thesis_without signatures.docx file_size: 5167703 relation: source_file file_date_updated: 2021-10-31T23:30:05Z has_accepted_license: '1' language: - iso: eng month: '04' oa: 1 oa_version: None page: '98' publication_identifier: eissn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '1028' relation: dissertation_contains status: public status: public supervisor: - first_name: Harald L full_name: Janovjak, Harald L id: 33BA6C30-F248-11E8-B48F-1D18A9856A87 last_name: Janovjak orcid: 0000-0002-8023-9315 title: Synthetic tools for optogenetic and chemogenetic inhibition of cellular signals type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2020' ... --- _id: '8620' abstract: - lang: eng text: "The development of the human brain occurs through a tightly regulated series of dynamic and adaptive processes during prenatal and postnatal life. A disruption of this strictly orchestrated series of events can lead to a number of neurodevelopmental conditions, including Autism Spectrum Disorders (ASDs). ASDs are a very common, etiologically and phenotypically heterogeneous group of disorders sharing the core symptoms of social interaction and communication deficits and restrictive and repetitive interests and behaviors. They are estimated to affect one in 59 individuals in the U.S. and, over the last three decades, mutations in more than a hundred genetic loci have been convincingly linked to ASD pathogenesis. Yet, for the vast majority of these ASD-risk genes their role during brain development and precise molecular function still remain elusive.\r\nDe novo loss of function mutations in the ubiquitin ligase-encoding gene Cullin 3 (CUL3) lead to ASD. In the study described here, we used Cul3 mouse models to evaluate the consequences of Cul3 mutations in vivo. Our results show that Cul3 heterozygous knockout mice exhibit deficits in motor coordination as well as ASD-relevant social and cognitive impairments. Cul3+/-, Cul3+/fl Emx1-Cre and Cul3fl/fl Emx1-Cre mutant brains display cortical lamination abnormalities due to defective migration of post-mitotic excitatory neurons, as well as reduced numbers of excitatory and inhibitory neurons. In line with the observed abnormal cortical organization, Cul3 heterozygous deletion is associated with decreased spontaneous excitatory and inhibitory activity in the cortex. At the molecular level we show that Cul3 regulates cytoskeletal and adhesion protein abundance in the mouse embryonic cortex. Abnormal regulation of cytoskeletal proteins in Cul3 mutant neural cells results in atypical organization of the actin mesh at the cell leading edge. Of note, heterozygous deletion of Cul3 in adult mice does not induce the majority of the behavioral defects observed in constitutive Cul3 haploinsufficient animals, pointing to a critical time-window for Cul3 deficiency.\r\nIn conclusion, our data indicate that Cul3 plays a critical role in the regulation of cytoskeletal proteins and neuronal migration. ASD-associated defects and behavioral abnormalities are primarily due to dosage sensitive Cul3 functions at early brain developmental stages." acknowledged_ssus: - _id: Bio - _id: PreCl acknowledgement: I would like to especially thank Armel Nicolas from the Proteomics and Christoph Sommer from the Bioimaging Facilities for the data analysis, and to thank the team of the Preclinical Facility, especially Sabina Deixler, Angela Schlerka, Anita Lepold, Mihalea Mihai and Michael Schun for taking care of the mouse line maintenance and their great support. alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Jasmin full_name: Morandell, Jasmin id: 4739D480-F248-11E8-B48F-1D18A9856A87 last_name: Morandell citation: ama: Morandell J. Illuminating the role of Cul3 in autism spectrum disorder pathogenesis. 2020. doi:10.15479/AT:ISTA:8620 apa: Morandell, J. (2020). Illuminating the role of Cul3 in autism spectrum disorder pathogenesis. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:8620 chicago: Morandell, Jasmin. “Illuminating the Role of Cul3 in Autism Spectrum Disorder Pathogenesis.” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:8620. ieee: J. Morandell, “Illuminating the role of Cul3 in autism spectrum disorder pathogenesis,” Institute of Science and Technology Austria, 2020. ista: Morandell J. 2020. Illuminating the role of Cul3 in autism spectrum disorder pathogenesis. Institute of Science and Technology Austria. mla: Morandell, Jasmin. Illuminating the Role of Cul3 in Autism Spectrum Disorder Pathogenesis. Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:8620. short: J. Morandell, Illuminating the Role of Cul3 in Autism Spectrum Disorder Pathogenesis, Institute of Science and Technology Austria, 2020. date_created: 2020-10-07T14:53:13Z date_published: 2020-10-12T00:00:00Z date_updated: 2023-09-07T13:22:14Z day: '12' ddc: - '610' degree_awarded: PhD department: - _id: GaNo doi: 10.15479/AT:ISTA:8620 file: - access_level: open_access checksum: 7ee83e42de3e5ce2fedb44dff472f75f content_type: application/pdf creator: jmorande date_created: 2020-10-07T14:41:49Z date_updated: 2021-10-16T22:30:04Z embargo: 2021-10-15 file_id: '8621' file_name: Jasmin_Morandell_Thesis-2020_final.pdf file_size: 16155786 relation: main_file - access_level: closed checksum: 5e0464af453734210ce7aab7b4a92e3a content_type: application/x-zip-compressed creator: jmorande date_created: 2020-10-07T14:45:07Z date_updated: 2021-10-16T22:30:04Z embargo_to: open_access file_id: '8622' file_name: Jasmin_Morandell_Thesis-2020_final.zip file_size: 24344152 relation: source_file file_date_updated: 2021-10-16T22:30:04Z has_accepted_license: '1' language: - iso: eng month: '10' oa: 1 oa_version: Published Version page: '138' project: - _id: 2548AE96-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: W1232-B24 name: Molecular Drug Targets - _id: 05A0D778-7A3F-11EA-A408-12923DDC885E grant_number: F07807 name: Neural stem cells in autism and epilepsy publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '7800' relation: part_of_dissertation status: public - id: '8131' relation: part_of_dissertation status: public status: public supervisor: - first_name: Gaia full_name: Novarino, Gaia id: 3E57A680-F248-11E8-B48F-1D18A9856A87 last_name: Novarino orcid: 0000-0002-7673-7178 title: Illuminating the role of Cul3 in autism spectrum disorder pathogenesis type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2020' ... --- _id: '8340' abstract: - lang: eng text: Mitochondria are sites of oxidative phosphorylation in eukaryotic cells. Oxidative phosphorylation operates by a chemiosmotic mechanism made possible by redox-driven proton pumping machines which establish a proton motive force across the inner mitochondrial membrane. This electrochemical proton gradient is used to drive ATP synthesis, which powers the majority of cellular processes such as protein synthesis, locomotion and signalling. In this thesis I investigate the structures and molecular mechanisms of two inner mitochondrial proton pumping enzymes, respiratory complex I and transhydrogenase. I present the first high-resolution structure of the full transhydrogenase from any species, and a significantly improved structure of complex I. Improving the resolution from 3.3 Å available previously to up to 2.3 Å in this thesis allowed us to model bound water molecules, crucial in the proton pumping mechanism. For both enzymes, up to five cryo-EM datasets with different substrates and inhibitors bound were solved to delineate the catalytic cycle and understand the proton pumping mechanism. In transhydrogenase, the proton channel is gated by reversible detachment of the NADP(H)-binding domain which opens the proton channel to the opposite sites of the membrane. In complex I, the proton channels are gated by reversible protonation of key glutamate and lysine residues and breaking of the water wire connecting the proton pumps with the quinone reduction site. The tight coupling between the redox and the proton pumping reactions in transhydrogenase is achieved by controlling the NADP(H) exchange which can only happen when the NADP(H)-binding domain interacts with the membrane domain. In complex I, coupling is achieved by cycling of the whole complex between the closed state, in which quinone can get reduced, and the open state, in which NADH can induce quinol ejection from the binding pocket. On the basis of these results I propose detailed mechanisms for catalytic cycles of transhydrogenase and complex I that are consistent with a large amount of previous work. In both enzymes, conformational and electrostatic mechanisms contribute to the overall catalytic process. Results presented here could be used for better understanding of the human pathologies arising from deficiencies of complex I or transhydrogenase and could be used to develop novel therapies. acknowledged_ssus: - _id: EM-Fac acknowledgement: 'I acknowledge the support of IST facilities, especially the Electron Miscroscopy facility for providing training and resources. Special thanks also go to cryo-EM specialists who helped me to collect the data present here: Dr Valentin Hodirnau (IST Austria), Dr Tom Heuser (IMBA, Vienna), Dr Rebecca Thompson (Uni. of Leeds) and Dr Jirka Nováček (CEITEC). This work has been supported by iNEXT, project number 653706, funded by the Horizon 2020 programme of the European Union. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant Agreement No. 665385.' alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Domen full_name: Kampjut, Domen id: 37233050-F248-11E8-B48F-1D18A9856A87 last_name: Kampjut citation: ama: Kampjut D. Molecular mechanisms of mitochondrial redox-coupled proton pumping enzymes. 2020. doi:10.15479/AT:ISTA:8340 apa: Kampjut, D. (2020). Molecular mechanisms of mitochondrial redox-coupled proton pumping enzymes. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:8340 chicago: Kampjut, Domen. “Molecular Mechanisms of Mitochondrial Redox-Coupled Proton Pumping Enzymes.” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:8340. ieee: D. Kampjut, “Molecular mechanisms of mitochondrial redox-coupled proton pumping enzymes,” Institute of Science and Technology Austria, 2020. ista: Kampjut D. 2020. Molecular mechanisms of mitochondrial redox-coupled proton pumping enzymes. Institute of Science and Technology Austria. mla: Kampjut, Domen. Molecular Mechanisms of Mitochondrial Redox-Coupled Proton Pumping Enzymes. Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:8340. short: D. Kampjut, Molecular Mechanisms of Mitochondrial Redox-Coupled Proton Pumping Enzymes, Institute of Science and Technology Austria, 2020. date_created: 2020-09-07T18:42:23Z date_published: 2020-09-09T00:00:00Z date_updated: 2023-09-07T13:26:17Z day: '09' ddc: - '572' degree_awarded: PhD department: - _id: LeSa doi: 10.15479/AT:ISTA:8340 ec_funded: 1 file: - access_level: closed checksum: dd270baf82121eb4472ad19d77bf227c content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: dkampjut date_created: 2020-09-08T13:32:06Z date_updated: 2021-09-11T22:30:04Z embargo_to: open_access file_id: '8345' file_name: ThesisFull20200908.docx file_size: 166146359 relation: source_file - access_level: open_access checksum: 82fce6f95ffa47ecc4ebca67ea2cc38c content_type: application/pdf creator: dernst date_created: 2020-09-14T15:02:20Z date_updated: 2021-09-11T22:30:04Z embargo: 2021-09-10 file_id: '8393' file_name: 2020_Thesis_Kampjut.pdf file_size: 13873769 relation: main_file file_date_updated: 2021-09-11T22:30:04Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: None page: '242' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: isbn: - 978-3-99078-008-4 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '6848' relation: part_of_dissertation status: public status: public supervisor: - first_name: Leonid A full_name: Sazanov, Leonid A id: 338D39FE-F248-11E8-B48F-1D18A9856A87 last_name: Sazanov orcid: 0000-0002-0977-7989 title: Molecular mechanisms of mitochondrial redox-coupled proton pumping enzymes type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2020' ...