--- _id: '11393' abstract: - lang: eng text: "AMPA receptors (AMPARs) mediate fast excitatory neurotransmission and their role is\r\nimplicated in complex processes such as learning and memory and various neurological\r\ndiseases. These receptors are composed of different subunits and the subunit composition can\r\naffect channel properties, receptor trafficking and interaction with other associated proteins.\r\nUsing the high sensitivity SDS-digested freeze-fracture replica labeling (SDS-FRL) for\r\nelectron microscopy I investigated the number, density, and localization of AMPAR subunits,\r\nGluA1, GluA2, GluA3, and GluA1-3 (panAMPA) in pyramidal cells in the CA1 area of mouse\r\nhippocampus. I have found that the immunogold labeling for all of these subunits in the\r\npostsynaptic sites was highest in stratum radiatum and lowest in stratum lacunosummoleculare. The labeling density for the all subunits in the extrasynaptic sites showed a gradual\r\nincrease from the pyramidal cell soma towards the distal part of stratum radiatum. The densities\r\nof extrasynaptic GluA1, GluA2 and panAMPA labeling reached 10-15% of synaptic densities,\r\nwhile the ratio of extrasynaptic labeling for GluA3 was significantly lower compared than those\r\nfor other subunits. The labeling patterns for GluA1, GluA2 and GluA1-3 are similar and their\r\ndensities were higher in the periphery than center of synapses. In contrast, the GluA3-\r\ncontaining receptors were more centrally localized compared to the GluA1- and GluA2-\r\ncontaining receptors.\r\nThe hippocampus plays a central role in learning and memory. Contextual learning has been\r\nshown to require the delivery of AMPA receptors to CA1 synapses in the dorsal hippocampus.\r\nHowever, proximodistal heterogeneity of this plasticity and particular contribution of different\r\nAMPA receptor subunits are not fully understood. By combining inhibitory avoidance task, a\r\nhippocampus-dependent contextual fear-learning paradigm, with SDS-FRL, I have revealed an\r\nincrease in synaptic density specific to GluA1-containing AMPA receptors in the CA1 area.\r\nThe intrasynaptic distribution of GluA1 also changed from the periphery to center-preferred\r\npattern. Furthermore, this synaptic plasticity was evident selectively in stratum radiatum but\r\nnot stratum oriens, and in the CA1 subregion proximal but not distal to CA2. These findings\r\nfurther contribute to our understanding of how specific hippocampal subregions and AMPA\r\nreceptor subunits are involved in physiological learning.\r\nAlthough the immunolabeling results above shed light on subunit-specific plasticity in\r\nAMPAR distribution, no tools to visualize and study the subunit composition at the single\r\nchannel level in situ have been available. Electron microscopy with conventional immunogold\r\nlabeling approaches has limitations in the single channel analysis because of the large size of\r\nantibodies and steric hindrance hampering multiple subunit labeling of single channels. I\r\nmanaged to develop a new chemical labeling system using a short peptide tag and small\r\nsynthetic probes, which form specific covalent bond with a cysteine residue in the tag fused to\r\nproteins of interest (reactive tag system). I additionally made substantial progress into adapting\r\nthis system for AMPA receptor subunits." acknowledged_ssus: - _id: EM-Fac alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Marijo full_name: Jevtic, Marijo id: 4BE3BC94-F248-11E8-B48F-1D18A9856A87 last_name: Jevtic citation: ama: Jevtic M. Contextual fear learning induced changes in AMPA receptor subtypes along the proximodistal axis in dorsal hippocampus. 2022. doi:10.15479/at:ista:11393 apa: Jevtic, M. (2022). Contextual fear learning induced changes in AMPA receptor subtypes along the proximodistal axis in dorsal hippocampus. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:11393 chicago: Jevtic, Marijo. “Contextual Fear Learning Induced Changes in AMPA Receptor Subtypes along the Proximodistal Axis in Dorsal Hippocampus.” Institute of Science and Technology Austria, 2022. https://doi.org/10.15479/at:ista:11393. ieee: M. Jevtic, “Contextual fear learning induced changes in AMPA receptor subtypes along the proximodistal axis in dorsal hippocampus,” Institute of Science and Technology Austria, 2022. ista: Jevtic M. 2022. Contextual fear learning induced changes in AMPA receptor subtypes along the proximodistal axis in dorsal hippocampus. Institute of Science and Technology Austria. mla: Jevtic, Marijo. Contextual Fear Learning Induced Changes in AMPA Receptor Subtypes along the Proximodistal Axis in Dorsal Hippocampus. Institute of Science and Technology Austria, 2022, doi:10.15479/at:ista:11393. short: M. Jevtic, Contextual Fear Learning Induced Changes in AMPA Receptor Subtypes along the Proximodistal Axis in Dorsal Hippocampus, Institute of Science and Technology Austria, 2022. date_created: 2022-05-17T08:57:41Z date_published: 2022-05-16T00:00:00Z date_updated: 2023-09-07T14:53:44Z day: '16' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: RySh doi: 10.15479/at:ista:11393 file: - access_level: closed checksum: 8fc695d88020d70d231dad0e9f10b138 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: cchlebak date_created: 2022-05-17T09:08:06Z date_updated: 2023-05-17T22:30:03Z embargo_to: open_access file_id: '11395' file_name: MJ thesis.docx file_size: 56427603 relation: source_file - access_level: open_access checksum: c1dd20a1aece521b3500607b00e463d6 content_type: application/pdf creator: cchlebak date_created: 2022-05-17T12:09:25Z date_updated: 2023-05-17T22:30:03Z embargo: 2023-05-16 file_id: '11397' file_name: MJ_thesis_PDFA.pdf file_size: 4351981 relation: main_file file_date_updated: 2023-05-17T22:30:03Z has_accepted_license: '1' language: - iso: eng month: '05' oa: 1 oa_version: Published Version page: '108' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '7391' relation: part_of_dissertation status: public 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: Contextual fear learning induced changes in AMPA receptor subtypes along the proximodistal axis in dorsal hippocampus type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2022' ... --- _id: '7391' abstract: - lang: eng text: Electron microscopy (EM) is a technology that enables visualization of single proteins at a nanometer resolution. However, current protein analysis by EM mainly relies on immunolabeling with gold-particle-conjugated antibodies, which is compromised by large size of antibody, precluding precise detection of protein location in biological samples. Here, we develop a specific chemical labeling method for EM detection of proteins at single-molecular level. Rational design of α-helical peptide tag and probe structure provided a complementary reaction pair that enabled specific cysteine conjugation of the tag. The developed chemical labeling with gold-nanoparticle-conjugated probe showed significantly higher labeling efficiency and detectability of high-density clusters of tag-fused G protein-coupled receptors in freeze-fracture replicas compared with immunogold labeling. Furthermore, in ultrathin sections, the spatial resolution of the chemical labeling was significantly higher than that of antibody-mediated labeling. These results demonstrate substantial advantages of the chemical labeling approach for single protein visualization by EM. article_processing_charge: No article_type: original author: - first_name: Shigekazu full_name: Tabata, Shigekazu id: 4427179E-F248-11E8-B48F-1D18A9856A87 last_name: Tabata - first_name: Marijo full_name: Jevtic, Marijo id: 4BE3BC94-F248-11E8-B48F-1D18A9856A87 last_name: Jevtic - first_name: Nobutaka full_name: Kurashige, Nobutaka last_name: Kurashige - first_name: Hirokazu full_name: Fuchida, Hirokazu last_name: Fuchida - first_name: Munetsugu full_name: Kido, Munetsugu last_name: Kido - first_name: Kazushi full_name: Tani, Kazushi last_name: Tani - first_name: Naoki full_name: Zenmyo, Naoki last_name: Zenmyo - first_name: Shohei full_name: Uchinomiya, Shohei last_name: Uchinomiya - first_name: Harumi full_name: Harada, Harumi id: 2E55CDF2-F248-11E8-B48F-1D18A9856A87 last_name: Harada orcid: 0000-0001-7429-7896 - first_name: Makoto full_name: Itakura, Makoto last_name: Itakura - first_name: Itaru full_name: Hamachi, Itaru last_name: Hamachi - first_name: Ryuichi full_name: Shigemoto, Ryuichi id: 499F3ABC-F248-11E8-B48F-1D18A9856A87 last_name: Shigemoto orcid: 0000-0001-8761-9444 - first_name: Akio full_name: Ojida, Akio last_name: Ojida citation: ama: Tabata S, Jevtic M, Kurashige N, et al. Electron microscopic detection of single membrane proteins by a specific chemical labeling. iScience. 2019;22(12):256-268. doi:10.1016/j.isci.2019.11.025 apa: Tabata, S., Jevtic, M., Kurashige, N., Fuchida, H., Kido, M., Tani, K., … Ojida, A. (2019). Electron microscopic detection of single membrane proteins by a specific chemical labeling. IScience. Elsevier. https://doi.org/10.1016/j.isci.2019.11.025 chicago: Tabata, Shigekazu, Marijo Jevtic, Nobutaka Kurashige, Hirokazu Fuchida, Munetsugu Kido, Kazushi Tani, Naoki Zenmyo, et al. “Electron Microscopic Detection of Single Membrane Proteins by a Specific Chemical Labeling.” IScience. Elsevier, 2019. https://doi.org/10.1016/j.isci.2019.11.025. ieee: S. Tabata et al., “Electron microscopic detection of single membrane proteins by a specific chemical labeling,” iScience, vol. 22, no. 12. Elsevier, pp. 256–268, 2019. ista: Tabata S, Jevtic M, Kurashige N, Fuchida H, Kido M, Tani K, Zenmyo N, Uchinomiya S, Harada H, Itakura M, Hamachi I, Shigemoto R, Ojida A. 2019. Electron microscopic detection of single membrane proteins by a specific chemical labeling. iScience. 22(12), 256–268. mla: Tabata, Shigekazu, et al. “Electron Microscopic Detection of Single Membrane Proteins by a Specific Chemical Labeling.” IScience, vol. 22, no. 12, Elsevier, 2019, pp. 256–68, doi:10.1016/j.isci.2019.11.025. short: S. Tabata, M. Jevtic, N. Kurashige, H. Fuchida, M. Kido, K. Tani, N. Zenmyo, S. Uchinomiya, H. Harada, M. Itakura, I. Hamachi, R. Shigemoto, A. Ojida, IScience 22 (2019) 256–268. date_created: 2020-01-29T15:56:56Z date_published: 2019-12-20T00:00:00Z date_updated: 2024-03-28T23:30:12Z day: '20' ddc: - '570' department: - _id: RySh doi: 10.1016/j.isci.2019.11.025 ec_funded: 1 external_id: isi: - :000504652000020 pmid: - '31786521' file: - access_level: open_access checksum: f3e90056a49f09b205b1c4f8c739ffd1 content_type: application/pdf creator: dernst date_created: 2020-02-04T10:48:36Z date_updated: 2020-07-14T12:47:57Z file_id: '7448' file_name: 2019_iScience_Tabata.pdf file_size: 7197776 relation: main_file file_date_updated: 2020-07-14T12:47:57Z has_accepted_license: '1' intvolume: ' 22' issue: '12' language: - iso: eng license: https://creativecommons.org/licenses/by/4.0/ month: '12' oa: 1 oa_version: Published Version page: 256-268 pmid: 1 project: - _id: 25CA28EA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694539' name: 'In situ analysis of single channel subunit composition in neurons: physiological implication in synaptic plasticity and behaviour' - _id: 25CBA828-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '720270' name: Human Brain Project Specific Grant Agreement 1 (HBP SGA 1) publication: iScience publication_identifier: issn: - 2589-0042 publication_status: published publisher: Elsevier quality_controlled: '1' related_material: record: - id: '11393' relation: dissertation_contains status: public scopus_import: '1' status: public title: Electron microscopic detection of single membrane proteins by a specific chemical labeling 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: journal_article user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 volume: 22 year: '2019' ...