--- _id: '6269' abstract: - lang: eng text: 'Clathrin-Mediated Endocytosis (CME) is an aspect of cellular trafficking that is constantly regulated for mediating developmental and physiological responses. The main aim of my thesis is to decipher the basic mechanisms of CME and post-endocytic trafficking in the whole multicellular organ systems of Arabidopsis. The first chapter of my thesis describes the search for new components involved in CME. Tandem affinity purification was conducted using CLC and its interacting partners were identified. Amongst the identified proteins were the Auxilin-likes1 and 2 (Axl1/2), putative uncoating factors, for which we made a full functional analysis. Over-expression of Axl1/2 causes extreme modifications in the dynamics of the machinery proteins and inhibition of endocytosis altogether. However the loss of function of the axl1/2 did not present any cellular or physiological phenotype, meaning Auxilin-likes do not form the major uncoating machinery. The second chapter of my thesis describes the establishment/utilisation of techniques to capture the dynamicity and the complexity of CME and post-endocytic trafficking. We have studied the development of endocytic pits at the PM – specifically, the mode of membrane remodeling during pit development and the role of actin in it, given plant cells possess high turgor pressure. Utilizing the improved z-resolution of TIRF and VAEM techniques, we captured the time-lapse of the endocytic events at the plasma membrane; and using particle detection software, we quantitatively analysed all the endocytic trajectories in an unbiased way to obtain the endocytic rate of the system. This together with the direct analysis of cargo internalisation from the PM provided an estimate on the endocytic potential of the cell. We also developed a methodology for ultrastructural analysis of different populations of Clathrin-Coated Structures (CCSs) in both PM and endomembranes in unroofed protoplasts. Structural analysis, together with the intensity profile of CCSs at the PM show that the mode of CCP development at the PM follows ‘Constant curvature model’; meaning that clathrin polymerisation energy is a major contributing factor of membrane remodeling. In addition, other analyses clearly show that actin is not required for membrane remodeling during invagination or any other step of CCP development, despite the prevalent high turgor pressure. However, actin is essential in orchestrating the post-endocytic trafficking of CCVs facilitating the EE formation. We also observed that the uncoating process post-endocytosis is not immediate; an alternative mechanism of uncoating – Sequential multi-step process – functions in the cell. Finally we also looked at one of the important physiological stimuli modulating the process – hormone, auxin. auxin has been known to influence CME before. We have made a detailed study on the concentration-time based effect of auxin on the machinery proteins, CCP development, and the specificity of cargoes endocytosed. To this end, we saw no general effect of auxin on CME at earlier time points. However, very low concentration of IAA, such as 50nM, accelerates endocytosis of specifically PIN2 through CME. Such a tight regulatory control with high specificity to PIN2 could be essential in modulating its polarity. ' acknowledged_ssus: - _id: Bio - _id: EM-Fac alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Madhumitha full_name: Narasimhan, Madhumitha id: 44BF24D0-F248-11E8-B48F-1D18A9856A87 last_name: Narasimhan orcid: 0000-0002-8600-0671 citation: ama: Narasimhan M. Clathrin-Mediated endocytosis, post-endocytic trafficking and their regulatory controls in plants . 2019. doi:10.15479/at:ista:th1075 apa: Narasimhan, M. (2019). Clathrin-Mediated endocytosis, post-endocytic trafficking and their regulatory controls in plants . Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:th1075 chicago: Narasimhan, Madhumitha. “Clathrin-Mediated Endocytosis, Post-Endocytic Trafficking and Their Regulatory Controls in Plants .” Institute of Science and Technology Austria, 2019. https://doi.org/10.15479/at:ista:th1075. ieee: M. Narasimhan, “Clathrin-Mediated endocytosis, post-endocytic trafficking and their regulatory controls in plants ,” Institute of Science and Technology Austria, 2019. ista: Narasimhan M. 2019. Clathrin-Mediated endocytosis, post-endocytic trafficking and their regulatory controls in plants . Institute of Science and Technology Austria. mla: Narasimhan, Madhumitha. Clathrin-Mediated Endocytosis, Post-Endocytic Trafficking and Their Regulatory Controls in Plants . Institute of Science and Technology Austria, 2019, doi:10.15479/at:ista:th1075. short: M. Narasimhan, Clathrin-Mediated Endocytosis, Post-Endocytic Trafficking and Their Regulatory Controls in Plants , Institute of Science and Technology Austria, 2019. date_created: 2019-04-09T14:37:06Z date_published: 2019-02-04T00:00:00Z date_updated: 2023-09-08T11:43:03Z day: '04' ddc: - '575' degree_awarded: PhD department: - _id: JiFr doi: 10.15479/at:ista:th1075 file: - access_level: open_access checksum: c958f27dd752712886e7e2638b847a3c content_type: video/x-msvideo creator: dernst date_created: 2019-04-09T14:35:18Z date_updated: 2021-02-11T23:30:15Z embargo: 2020-02-11 file_id: '6270' file_name: Supplementary_movie_1.avi file_size: 5402078 relation: main_file - access_level: open_access checksum: 8786fdc29c62987c0aad3c866a4d3691 content_type: video/x-msvideo creator: dernst date_created: 2019-04-09T14:35:18Z date_updated: 2021-02-11T23:30:15Z embargo: 2020-02-11 file_id: '6271' file_name: 3.7_supplementary_movie_10.avi file_size: 5927736 relation: main_file - access_level: open_access checksum: 25f784c5159d6f4d966b2f9b371ebaf6 content_type: video/x-msvideo creator: dernst date_created: 2019-04-09T14:35:18Z date_updated: 2021-02-11T23:30:15Z embargo: 2020-02-11 file_id: '6272' file_name: 3.7_supplementary_movie_9.avi file_size: 9570210 relation: main_file - 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access_level: open_access checksum: 4fcdaa3a6c645514a3b3205f0f69dc76 content_type: application/pdf creator: dernst date_created: 2019-04-09T14:35:33Z date_updated: 2021-02-11T11:17:15Z embargo: 2020-02-11 file_id: '6285' file_name: 2019_Thesis_Narasimhan.pdf file_size: 10553937 relation: main_file - access_level: closed checksum: 268f0b6bad21d5f0d671e5d4b88104a7 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: dernst date_created: 2019-04-09T14:35:36Z date_updated: 2020-07-14T12:47:26Z embargo_to: open_access file_id: '6286' file_name: 2019_Thesis_Narasimhan_source.docx file_size: 135291990 relation: source_file file_date_updated: 2021-02-11T23:30:15Z has_accepted_license: '1' language: - iso: eng license: https://creativecommons.org/licenses/by/4.0/ month: '02' oa: 1 oa_version: Published Version page: '138' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '412' relation: part_of_dissertation status: public status: public supervisor: - first_name: Jiří full_name: Friml, Jiří id: 4159519E-F248-11E8-B48F-1D18A9856A87 last_name: Friml orcid: 0000-0002-8302-7596 title: 'Clathrin-Mediated endocytosis, post-endocytic trafficking and their regulatory controls in plants ' tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2019' ... --- _id: '6435' abstract: - lang: eng text: "Social insect colonies tend to have numerous members which function together like a single organism in such harmony that the term ``super-organism'' is often used. In this analogy the reproductive caste is analogous to the primordial germ\r\ncells of a metazoan, while the sterile worker caste corresponds to somatic cells. The worker castes, like tissues, are\r\nin charge of all functions of a living being, besides reproduction. The establishment of new super-organismal units\r\n(i.e. new colonies) is accomplished by the co-dependent castes. The term oftentimes goes beyond a metaphor. We invoke it when we speak about the metabolic rate, thermoregulation, nutrient regulation and gas exchange of a social insect colony. Furthermore, we assert that the super-organism has an immune system, and benefits from ``social immunity''.\r\n\r\nSocial immunity was first summoned by evolutionary biologists to resolve the apparent discrepancy between the expected high frequency of disease outbreak amongst numerous, closely related tightly-interacting hosts, living in stable and microbially-rich environments, against the exceptionally scarce epidemic accounts in natural populations. Social\r\nimmunity comprises a multi-layer assembly of behaviours which have evolved to effectively keep the pathogenic enemies of a colony at bay. The field of social immunity has drawn interest, as it becomes increasingly urgent to stop\r\nthe collapse of pollinator species and curb the growth of invasive pests. In the past decade, several mechanisms of\r\nsocial immune responses have been dissected, but many more questions remain open.\r\n\r\nI present my work in two experimental chapters. In the first, I use invasive garden ants (*Lasius neglectus*) to study how pathogen load and its distribution among nestmates affect the grooming response of the group. Any given group of ants will carry out the same total grooming work, but will direct their grooming effort towards individuals\r\ncarrying a relatively higher spore load. Contrary to expectation, the highest risk of transmission does not stem from grooming highly contaminated ants, but instead, we suggest that the grooming response likely minimizes spore loss to the environment, reducing contamination from inadvertent pickup from the substrate.\r\n\r\nThe second is a comparative developmental approach. I follow black garden ant queens (*Lasius niger*) and their colonies from mating flight, through hibernation for a year. Colonies which grow fast from the start, have a lower chance of survival through hibernation, and those which survive grow at a lower pace later. This is true for colonies of naive\r\nand challenged queens. Early pathogen exposure of the queens changes colony dynamics in an unexpected way: colonies from exposed queens are more likely to grow slowly and recover in numbers only after they survive hibernation.\r\n\r\nIn addition to the two experimental chapters, this thesis includes a co-authored published review on organisational\r\nimmunity, where we enlist the experimental evidence and theoretical framework on which this hypothesis is built,\r\nidentify the caveats and underline how the field is ripe to overcome them. In a final chapter, I describe my part in\r\ntwo collaborative efforts, one to develop an image-based tracker, and the second to develop a classifier for ant\r\nbehaviour." acknowledged_ssus: - _id: Bio - _id: ScienComp - _id: M-Shop - _id: LifeSc alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Barbara E full_name: Casillas Perez, Barbara E id: 351ED2AA-F248-11E8-B48F-1D18A9856A87 last_name: Casillas Perez citation: ama: Casillas Perez BE. Collective defenses of garden ants against a fungal pathogen. 2019. doi:10.15479/AT:ISTA:6435 apa: Casillas Perez, B. E. (2019). Collective defenses of garden ants against a fungal pathogen. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:6435 chicago: Casillas Perez, Barbara E. “Collective Defenses of Garden Ants against a Fungal Pathogen.” Institute of Science and Technology Austria, 2019. https://doi.org/10.15479/AT:ISTA:6435. ieee: B. E. Casillas Perez, “Collective defenses of garden ants against a fungal pathogen,” Institute of Science and Technology Austria, 2019. ista: Casillas Perez BE. 2019. Collective defenses of garden ants against a fungal pathogen. Institute of Science and Technology Austria. mla: Casillas Perez, Barbara E. Collective Defenses of Garden Ants against a Fungal Pathogen. Institute of Science and Technology Austria, 2019, doi:10.15479/AT:ISTA:6435. short: B.E. Casillas Perez, Collective Defenses of Garden Ants against a Fungal Pathogen, Institute of Science and Technology Austria, 2019. date_created: 2019-05-13T08:58:35Z date_published: 2019-05-07T00:00:00Z date_updated: 2023-09-07T12:57:04Z day: '07' ddc: - '570' - '006' - '578' - '592' degree_awarded: PhD department: - _id: SyCr doi: 10.15479/AT:ISTA:6435 ec_funded: 1 file: - access_level: open_access checksum: 6daf2d2086111aa8fd3fbc919a3e2833 content_type: application/pdf creator: casillas date_created: 2019-05-13T09:16:20Z date_updated: 2021-02-11T11:17:15Z embargo: 2020-05-08 file_id: '6438' file_name: tesisDoctoradoBC.pdf file_size: 3895187 relation: main_file - access_level: closed checksum: 3d221aaff7559a7060230a1ff610594f content_type: application/zip creator: casillas date_created: 2019-05-13T09:16:20Z date_updated: 2020-07-14T12:47:30Z embargo_to: open_access file_id: '6439' file_name: tesisDoctoradoBC.zip file_size: 7365118 relation: source_file file_date_updated: 2021-02-11T11:17:15Z has_accepted_license: '1' keyword: - Social Immunity - Sanitary care - Social Insects - Organisational Immunity - Colony development - Multi-target tracking language: - iso: eng month: '05' oa: 1 oa_version: Published Version page: '183' project: - _id: 2649B4DE-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '771402' name: Epidemics in ant societies on a chip publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '1999' relation: part_of_dissertation status: public status: public supervisor: - first_name: Sylvia M full_name: Cremer, Sylvia M id: 2F64EC8C-F248-11E8-B48F-1D18A9856A87 last_name: Cremer orcid: 0000-0002-2193-3868 title: Collective defenses of garden ants against a fungal pathogen type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2019' ... --- _id: '6947' abstract: - lang: eng text: Lymph nodes are es s ential organs of the immune s ys tem where adaptive immune responses originate, and consist of various leukocyte populations and a stromal backbone. Fibroblastic reticular cells (FRCs) are the main stromal cells and form a sponge-like extracellular matrix network, called conduits , which they thems elves enwrap and contract. Lymph, containing s oluble antigens , arrive in lymph nodes via afferent lymphatic vessels that connect to the s ubcaps ular s inus and conduit network. According to the current paradigm, the conduit network dis tributes afferent lymph through lymph nodes and thus provides acces s for immune cells to lymph-borne antigens. An elas tic caps ule s urrounds the organ and confines the immune cells and FRC network. Lymph nodes are completely packed with lymphocytes and lymphocyte numbers directly dictates the size of the organ. Although lymphocytes cons tantly enter and leave the lymph node, its s ize remains remarkedly s table under homeostatic conditions. It is only partly known how the cellularity and s ize of the lymph node is regulated and how the lymph node is able to swell in inflammation. The role of the FRC network in lymph node s welling and trans fer of fluids are inves tigated in this thes is. Furthermore, we s tudied what trafficking routes are us ed by cancer cells in lymph nodes to form distal metastases.We examined the role of a mechanical feedback in regulation of lymph node swelling. Using parallel plate compression and UV-las er cutting experiments we dis s ected the mechanical force dynamics of the whole lymph node, and individually for FRCs and the caps ule. Physical forces generated by packed lymphocytes directly affect the tens ion on the FRC network and capsule, which increases its resistance to swelling. This implies a feedback mechanism between tis s ue pres s ure and ability of lymphocytes to enter the organ. Following inflammation, the lymph node swells ∼10 fold in two weeks . Yet, what is the role for tens ion on the FRC network and caps ule, and how are lymphocytes able to enter in conditions that resist swelling remain open ques tions . We s how that tens ion on the FRC network is important to limit the swelling rate of the organ so that the FRC network can grow in a coordinated fashion. This is illustrated by interfering with FRC contractility, which leads to faster swelling rates and a dis organized FRC network in the inflamed lymph node. Growth of the FRC network in turn is expected to releas e tens ion on thes e s tructures and lowers the res is tance to swelling, thereby allowing more lymphocytes to enter the organ and drive more swelling. Halt of swelling coincides with a thickening of the caps ule, which forms a thick res is tant band around the organ and lowers tens ion on the FRC network to form a new force equilibrium.The FRC and conduit network are further believed to be a privileged s ite of s oluble information within the lymph node, although many details remain uns olved. We s how by 3D ultra-recons truction that FRCs and antigen pres enting cells cover the s urface of conduit s ys tem for more than 99% and we dis cus s the implications for s oluble information exchangeat the conduit level.Finally, there is an ongoing debate in the cancer field whether and how cancer cells in lymph nodes s eed dis tal metas tas es . We s how that cancer cells infus ed into the lymph node can utilize trafficking routes of immune cells and rapidly migrate to blood vessels. Once in the blood circulation, these cells are able to form metastases in distal tissues. acknowledged_ssus: - _id: Bio - _id: PreCl - _id: EM-Fac alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Frank P full_name: Assen, Frank P id: 3A8E7F24-F248-11E8-B48F-1D18A9856A87 last_name: Assen orcid: 0000-0003-3470-6119 citation: ama: 'Assen FP. Lymph node mechanics: Deciphering the interplay between stroma contractility, morphology and lymphocyte trafficking. 2019. doi:10.15479/AT:ISTA:6947' apa: 'Assen, F. P. (2019). Lymph node mechanics: Deciphering the interplay between stroma contractility, morphology and lymphocyte trafficking. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:6947' chicago: 'Assen, Frank P. “Lymph Node Mechanics: Deciphering the Interplay between Stroma Contractility, Morphology and Lymphocyte Trafficking.” Institute of Science and Technology Austria, 2019. https://doi.org/10.15479/AT:ISTA:6947.' ieee: 'F. P. Assen, “Lymph node mechanics: Deciphering the interplay between stroma contractility, morphology and lymphocyte trafficking,” Institute of Science and Technology Austria, 2019.' ista: 'Assen FP. 2019. Lymph node mechanics: Deciphering the interplay between stroma contractility, morphology and lymphocyte trafficking. Institute of Science and Technology Austria.' mla: 'Assen, Frank P. Lymph Node Mechanics: Deciphering the Interplay between Stroma Contractility, Morphology and Lymphocyte Trafficking. Institute of Science and Technology Austria, 2019, doi:10.15479/AT:ISTA:6947.' short: 'F.P. Assen, Lymph Node Mechanics: Deciphering the Interplay between Stroma Contractility, Morphology and Lymphocyte Trafficking, Institute of Science and Technology Austria, 2019.' date_created: 2019-10-14T16:54:52Z date_published: 2019-10-09T00:00:00Z date_updated: 2023-09-13T08:50:57Z day: '9' ddc: - '570' degree_awarded: PhD department: - _id: MiSi doi: 10.15479/AT:ISTA:6947 file: - access_level: closed checksum: 53a739752a500f84d0f8ec953cbbd0b6 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: fassen date_created: 2019-11-06T12:30:02Z date_updated: 2020-11-07T23:30:03Z embargo_to: open_access file_id: '6990' file_name: PhDthesis_FrankAssen_revised2.docx file_size: 214172667 relation: source_file - access_level: open_access checksum: 8c156b65d9347bb599623a4b09f15d15 content_type: application/pdf creator: fassen date_created: 2019-11-06T12:30:57Z date_updated: 2020-11-07T23:30:03Z embargo: 2020-11-06 file_id: '6991' file_name: PhDthesis_FrankAssen_revised2.pdf file_size: 83637532 relation: main_file file_date_updated: 2020-11-07T23:30:03Z has_accepted_license: '1' language: - iso: eng month: '10' oa: 1 oa_version: Published Version page: '142' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '664' relation: part_of_dissertation status: public - id: '402' relation: part_of_dissertation status: public status: public supervisor: - first_name: Michael K full_name: Sixt, Michael K id: 41E9FBEA-F248-11E8-B48F-1D18A9856A87 last_name: Sixt orcid: 0000-0002-6620-9179 title: 'Lymph node mechanics: Deciphering the interplay between stroma contractility, morphology and lymphocyte trafficking' type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2019' ... --- _id: '6849' abstract: - lang: eng text: 'Brain function is mediated by complex dynamical interactions between excitatory and inhibitory cell types. The Cholecystokinin-expressing inhibitory cells (CCK-interneurons) are one of the least studied types, despite being suspected to play important roles in cognitive processes. We studied the network effects of optogenetic silencing of CCK-interneurons in the CA1 hippocampal area during exploration and sleep states. The cell firing pattern in response to light pulses allowed us to classify the recorded neurons in 5 classes, including disinhibited and non-responsive pyramidal cell and interneurons, and the inhibited interneurons corresponding to the CCK group. The light application, which inhibited the activity of CCK interneurons triggered wider changes in the firing dynamics of cells. We observed rate changes (i.e. remapping) of pyramidal cells during the exploration session in which the light was applied relative to the previous control session that was not restricted neither in time nor space to the light delivery. Also, the disinhibited pyramidal cells had higher increase in bursting than in single spike firing rate as a result of CCK silencing. In addition, the firing activity patterns during exploratory periods were more weakly reactivated in sleep for those periods in which CCK-interneuron were silenced than in the unaffected periods. Furthermore, light pulses during sleep disrupted the reactivation of recent waking patterns. Hence, silencing CCK neurons during exploration suppressed the reactivation of waking firing patterns in sleep and CCK interneuron activity was also required during sleep for the normal reactivation of waking patterns. These findings demonstrate the involvement of CCK cells in reactivation-related memory consolidation. An important part of our analysis was to test the relationship of the identified CCKinterneurons to brain oscillations. Our findings showed that these cells exhibited different oscillatory behaviour during anaesthesia and natural waking and sleep conditions. We showed that: 1) Contrary to the past studies performed under anaesthesia, the identified CCKinterneurons fired on the descending portion of the theta phase in waking exploration. 2) CCKinterneuron preferred phases around the trough of gamma oscillations. 3) Contrary to anaesthesia conditions, the average firing rate of the CCK-interneurons increased around the peak activity of the sharp-wave ripple (SWR) events in natural sleep, which is congruent with new reports about their functional connectivity. We also found that light driven CCK-interneuron silencing altered the dynamics on the CA1 network oscillatory activity: 1) Pyramidal cells negatively shifted their preferred theta phases when the light was applied, while interneurons responses were less consistent. 2) As a population, pyramidal cells negatively shifted their preferred activity during gamma oscillations, albeit we did not find gamma modulation differences related to the light application when pyramidal cells were subdivided into the disinhibited and unaffected groups. 3) During the peak of SWR events, all but the CCK-interneurons had a reduction in their relative firing rate change during the light application as compared to the change observed at SWR initiation. Finally, regarding to the place field activity of the recorded pyramidal neurons, we showed that the disinhibited pyramidal cells had reduced place field similarity, coherence and spatial information, but only during the light application. The mechanisms behind such observed behaviours might involve eCB signalling and plastic changes in CCK-interneuron synapses. In conclusion, the observed changes related to the light-mediated silencing of CCKinterneurons have unravelled characteristics of this interneuron subpopulation that might change the understanding not only of their particular network interactions, but also of the current theories about the emergence of certain cognitive processes such as place coding needed for navigation or hippocampus-dependent memory consolidation. ' acknowledged_ssus: - _id: Bio - _id: PreCl - _id: M-Shop alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Dámaris K full_name: Rangel Guerrero, Dámaris K id: 4871BCE6-F248-11E8-B48F-1D18A9856A87 last_name: Rangel Guerrero orcid: 0000-0002-8602-4374 citation: ama: Rangel Guerrero DK. The role of CCK-interneurons in regulating hippocampal network dynamics. 2019. doi:10.15479/AT:ISTA:6849 apa: Rangel Guerrero, D. K. (2019). The role of CCK-interneurons in regulating hippocampal network dynamics. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:6849 chicago: Rangel Guerrero, Dámaris K. “The Role of CCK-Interneurons in Regulating Hippocampal Network Dynamics.” Institute of Science and Technology Austria, 2019. https://doi.org/10.15479/AT:ISTA:6849. ieee: D. K. Rangel Guerrero, “The role of CCK-interneurons in regulating hippocampal network dynamics,” Institute of Science and Technology Austria, 2019. ista: Rangel Guerrero DK. 2019. The role of CCK-interneurons in regulating hippocampal network dynamics. Institute of Science and Technology Austria. mla: Rangel Guerrero, Dámaris K. The Role of CCK-Interneurons in Regulating Hippocampal Network Dynamics. Institute of Science and Technology Austria, 2019, doi:10.15479/AT:ISTA:6849. short: D.K. Rangel Guerrero, The Role of CCK-Interneurons in Regulating Hippocampal Network Dynamics, Institute of Science and Technology Austria, 2019. date_created: 2019-09-06T06:54:16Z date_published: 2019-09-09T00:00:00Z date_updated: 2023-09-19T10:01:12Z day: '09' ddc: - '570' degree_awarded: PhD department: - _id: JoCs doi: 10.15479/AT:ISTA:6849 file: - access_level: closed checksum: 244dc4f74dbfc94f414156092298831f content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: drangel date_created: 2019-09-09T13:09:45Z date_updated: 2021-02-10T23:30:09Z embargo_to: open_access file_id: '6865' file_name: Thesis_Damaris_Rangel_source.docx file_size: 18253100 relation: source_file - access_level: open_access checksum: 59c73be40eeaa1c4db24067270151555 content_type: application/pdf creator: drangel date_created: 2019-09-09T13:09:52Z date_updated: 2020-09-11T22:30:04Z embargo: 2020-09-10 file_id: '6866' file_name: Thesis_Damaris_Rangel_pdfa.pdf file_size: 2160109 relation: main_file request_a_copy: 0 file_date_updated: 2021-02-10T23:30:09Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '97' publication_identifier: isbn: - '9783990780039' issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '5914' relation: part_of_dissertation status: public status: public supervisor: - first_name: Jozsef L full_name: Csicsvari, Jozsef L id: 3FA14672-F248-11E8-B48F-1D18A9856A87 last_name: Csicsvari orcid: 0000-0002-5193-4036 title: The role of CCK-interneurons in regulating hippocampal network dynamics type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2019' ... --- _id: '7132' abstract: - lang: eng text: "A major challenge in neuroscience research is to dissect the circuits that orchestrate behavior in health and disease. Proteins from a wide range of non-mammalian species, such as microbial opsins, have been successfully transplanted to specific neuronal targets to override their natural communication patterns. The goal of our work is to manipulate synaptic communication in a manner that closely incorporates the functional intricacies of synapses by preserving temporal encoding (i.e. the firing pattern of the presynaptic neuron) and connectivity (i.e. target specific synapses rather than specific neurons). Our strategy to achieve this goal builds on the use of non-mammalian transplants to create a synthetic synapse. The mode of modulation comes from pre-synaptic uptake of a synthetic neurotransmitter (SN) into synaptic vesicles by means of a genetically targeted transporter selective for the SN. Upon natural vesicular release, exposure of the SN to the synaptic cleft will modify the post-synaptic potential through an orthogonal ligand gated ion channel. To achieve this goal we have functionally characterized a mixed cationic methionine-gated ion channel from Arabidopsis thaliana, designed a method to functionally characterize a synthetic transporter in isolated synaptic vesicles without the need for transgenic animals, identified and extracted multiple prokaryotic uptake systems that are substrate specific for methionine (Met), and established a primary/cell line co-culture system that would allow future combinatorial testing of this orthogonal transmitter-transporter-channel trifecta.\r\nSynthetic synapses will provide a unique opportunity to manipulate synaptic communication while maintaining the electrophysiological integrity of the pre-synaptic cell. In this way, information may be preserved that was generated in upstream circuits and that could be essential for concerted function and information processing." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Catherine full_name: Mckenzie, Catherine id: 3EEDE19A-F248-11E8-B48F-1D18A9856A87 last_name: Mckenzie citation: ama: Mckenzie C. Design and characterization of methods and biological components to realize synthetic neurotransmission. 2019. doi:10.15479/at:ista:7132 apa: Mckenzie, C. (2019). Design and characterization of methods and biological components to realize synthetic neurotransmission. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:7132 chicago: Mckenzie, Catherine. “Design and Characterization of Methods and Biological Components to Realize Synthetic Neurotransmission.” Institute of Science and Technology Austria, 2019. https://doi.org/10.15479/at:ista:7132. ieee: C. Mckenzie, “Design and characterization of methods and biological components to realize synthetic neurotransmission,” Institute of Science and Technology Austria, 2019. ista: Mckenzie C. 2019. Design and characterization of methods and biological components to realize synthetic neurotransmission. Institute of Science and Technology Austria. mla: Mckenzie, Catherine. Design and Characterization of Methods and Biological Components to Realize Synthetic Neurotransmission. Institute of Science and Technology Austria, 2019, doi:10.15479/at:ista:7132. short: C. Mckenzie, Design and Characterization of Methods and Biological Components to Realize Synthetic Neurotransmission, Institute of Science and Technology Austria, 2019. date_created: 2019-11-27T09:07:14Z date_published: 2019-06-27T00:00:00Z date_updated: 2024-03-18T23:30:22Z day: '27' ddc: - '571' - '573' degree_awarded: PhD department: - _id: HaJa doi: 10.15479/at:ista:7132 file: - access_level: closed checksum: 34d0fe0f6e0af97b5937205a3e350423 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: dernst date_created: 2019-11-27T09:06:10Z date_updated: 2020-07-14T12:47:50Z file_id: '7133' file_name: McKenzie PhD Thesis August 2018 - Corrected Final.docx file_size: 5054633 relation: source_file - access_level: open_access checksum: 140dfb5e3df7edca34f4b6fcc55d876f content_type: application/pdf creator: dernst date_created: 2019-11-27T09:06:10Z date_updated: 2020-07-14T12:47:50Z file_id: '7134' file_name: McKenzie PhD Thesis August 2018 - Corrected Final.pdf file_size: 3231837 relation: main_file file_date_updated: 2020-07-14T12:47:50Z has_accepted_license: '1' language: - iso: eng month: '06' oa: 1 oa_version: Published Version page: '95' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '6266' relation: old_edition 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: Design and characterization of methods and biological components to realize synthetic neurotransmission type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2019' ...