[{"has_accepted_license":"1","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png","short":"CC BY (4.0)"},"intvolume":"        14","abstract":[{"text":"Junctions between the endoplasmic reticulum (ER) and the plasma membrane (PM) are specialized membrane contacts ubiquitous in eukaryotic cells. Concentration of intracellular signaling machinery near ER-PM junctions allows these domains to serve critical roles in lipid and Ca2+ signaling and homeostasis. Subcellular compartmentalization of protein kinase A (PKA) signaling also regulates essential cellular functions, however, no specific association between PKA and ER-PM junctional domains is known. Here, we show that in brain neurons type I PKA is directed to Kv2.1 channel-dependent ER-PM junctional domains via SPHKAP, a type I PKA-specific anchoring protein. SPHKAP association with type I PKA regulatory subunit RI and ER-resident VAP proteins results in the concentration of type I PKA between stacked ER cisternae associated with ER-PM junctions. This ER-associated PKA signalosome enables reciprocal regulation between PKA and Ca2+ signaling machinery to support Ca2+ influx and excitation-transcription coupling. These data reveal that neuronal ER-PM junctions support a receptor-independent form of PKA signaling driven by membrane depolarization and intracellular Ca2+, allowing conversion of information encoded in electrical signals into biochemical changes universally recognized throughout the cell.","lang":"eng"}],"publication_identifier":{"eissn":["2041-1723"]},"publication_status":"published","file_date_updated":"2023-09-06T06:50:07Z","author":[{"last_name":"Vierra","full_name":"Vierra, Nicholas C.","first_name":"Nicholas C."},{"first_name":"Luisa","last_name":"Ribeiro-Silva","full_name":"Ribeiro-Silva, Luisa"},{"last_name":"Kirmiz","full_name":"Kirmiz, Michael","first_name":"Michael"},{"first_name":"Deborah","last_name":"Van Der List","full_name":"Van Der List, Deborah"},{"orcid":"0000-0003-0863-4481","first_name":"Pradeep","full_name":"Bhandari, Pradeep","id":"45EDD1BC-F248-11E8-B48F-1D18A9856A87","last_name":"Bhandari"},{"last_name":"Mack","full_name":"Mack, Olivia A.","first_name":"Olivia A."},{"first_name":"James","last_name":"Carroll","full_name":"Carroll, James"},{"first_name":"Elodie","last_name":"Le Monnier","id":"3B59276A-F248-11E8-B48F-1D18A9856A87","full_name":"Le Monnier, Elodie"},{"full_name":"Aicher, Sue A.","last_name":"Aicher","first_name":"Sue A."},{"orcid":"0000-0001-8761-9444","first_name":"Ryuichi","last_name":"Shigemoto","full_name":"Shigemoto, Ryuichi","id":"499F3ABC-F248-11E8-B48F-1D18A9856A87"},{"first_name":"James S.","full_name":"Trimmer, James S.","last_name":"Trimmer"}],"day":"26","scopus_import":"1","title":"Neuronal ER-plasma membrane junctions couple excitation to Ca2+-activated PKA signaling","oa_version":"Published Version","volume":14,"article_type":"original","date_created":"2023-09-03T22:01:14Z","oa":1,"language":[{"iso":"eng"}],"citation":{"mla":"Vierra, Nicholas C., et al. “Neuronal ER-Plasma Membrane Junctions Couple Excitation to Ca2+-Activated PKA Signaling.” <i>Nature Communications</i>, vol. 14, 5231, Springer Nature, 2023, doi:<a href=\"https://doi.org/10.1038/s41467-023-40930-6\">10.1038/s41467-023-40930-6</a>.","apa":"Vierra, N. C., Ribeiro-Silva, L., Kirmiz, M., Van Der List, D., Bhandari, P., Mack, O. A., … Trimmer, J. S. (2023). Neuronal ER-plasma membrane junctions couple excitation to Ca2+-activated PKA signaling. <i>Nature Communications</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41467-023-40930-6\">https://doi.org/10.1038/s41467-023-40930-6</a>","ista":"Vierra NC, Ribeiro-Silva L, Kirmiz M, Van Der List D, Bhandari P, Mack OA, Carroll J, Le Monnier E, Aicher SA, Shigemoto R, Trimmer JS. 2023. Neuronal ER-plasma membrane junctions couple excitation to Ca2+-activated PKA signaling. Nature Communications. 14, 5231.","chicago":"Vierra, Nicholas C., Luisa Ribeiro-Silva, Michael Kirmiz, Deborah Van Der List, Pradeep Bhandari, Olivia A. Mack, James Carroll, et al. “Neuronal ER-Plasma Membrane Junctions Couple Excitation to Ca2+-Activated PKA Signaling.” <i>Nature Communications</i>. Springer Nature, 2023. <a href=\"https://doi.org/10.1038/s41467-023-40930-6\">https://doi.org/10.1038/s41467-023-40930-6</a>.","short":"N.C. Vierra, L. Ribeiro-Silva, M. Kirmiz, D. Van Der List, P. Bhandari, O.A. Mack, J. Carroll, E. Le Monnier, S.A. Aicher, R. Shigemoto, J.S. Trimmer, Nature Communications 14 (2023).","ieee":"N. C. Vierra <i>et al.</i>, “Neuronal ER-plasma membrane junctions couple excitation to Ca2+-activated PKA signaling,” <i>Nature Communications</i>, vol. 14. Springer Nature, 2023.","ama":"Vierra NC, Ribeiro-Silva L, Kirmiz M, et al. Neuronal ER-plasma membrane junctions couple excitation to Ca2+-activated PKA signaling. <i>Nature Communications</i>. 2023;14. doi:<a href=\"https://doi.org/10.1038/s41467-023-40930-6\">10.1038/s41467-023-40930-6</a>"},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","month":"08","department":[{"_id":"RySh"}],"article_number":"5231","file":[{"relation":"main_file","checksum":"6ab8aab4e957f626a09a1c73db3388fb","success":1,"file_name":"2023_NatureComm_Vierra.pdf","access_level":"open_access","content_type":"application/pdf","file_id":"14270","file_size":9412549,"date_created":"2023-09-06T06:50:07Z","date_updated":"2023-09-06T06:50:07Z","creator":"dernst"}],"ddc":["570"],"quality_controlled":"1","doi":"10.1038/s41467-023-40930-6","article_processing_charge":"Yes","publisher":"Springer Nature","date_updated":"2023-09-06T06:53:32Z","_id":"14253","type":"journal_article","publication":"Nature Communications","status":"public","pmid":1,"date_published":"2023-08-26T00:00:00Z","acknowledgement":"We thank Kayla Templeton and Peter Turcanu for technical assistance, Michelle Salemi for assistance with LC-MS data acquisition and analysis, Dr. Belvin Gong for advice on monoclonal antibody generation, Drs. Maria Casas Prat and Eamonn Dickson for assistance with super-resolution TIRF microscopy, Dr. Oscar Cerda for assistance with the design of TAT-FFAT peptides, Dr. Fernando Santana for helpful discussions, and Dr. Jodi Nunnari for a careful reading of our manuscript. We also thank Dr. Alan Howe, Dr. Sohum Mehta, and Dr. Jin Zhang for providing plasmids used in this study. This project was funded by NIH Grants R01NS114210 and R21NS101648 (J.S.T.), and F32NS108519 (N.C.V.).","year":"2023","external_id":{"pmid":["37633939"]}},{"publication_status":"published","publication_identifier":{"eissn":["2050-084X"]},"file_date_updated":"2021-05-31T09:43:09Z","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png","short":"CC BY (4.0)"},"intvolume":"        10","abstract":[{"text":"The synaptic connection from medial habenula (MHb) to interpeduncular nucleus (IPN) is critical for emotion-related behaviors and uniquely expresses R-type Ca2+ channels (Cav2.3) and auxiliary GABAB receptor (GBR) subunits, the K+-channel tetramerization domain-containing proteins (KCTDs). Activation of GBRs facilitates or inhibits transmitter release from MHb terminals depending on the IPN subnucleus, but the role of KCTDs is unknown. We therefore examined the localization and function of Cav2.3, GBRs, and KCTDs in this pathway in mice. We show in heterologous cells that KCTD8 and KCTD12b directly bind to Cav2.3 and that KCTD8 potentiates Cav2.3 currents in the absence of GBRs. In the rostral IPN, KCTD8, KCTD12b, and Cav2.3 co-localize at the presynaptic active zone. Genetic deletion indicated a bidirectional modulation of Cav2.3-mediated release by these KCTDs with a compensatory increase of KCTD8 in the active zone in KCTD12b-deficient mice. The interaction of Cav2.3 with KCTDs therefore scales synaptic strength independent of GBR activation.","lang":"eng"}],"has_accepted_license":"1","article_type":"original","date_created":"2021-05-30T22:01:23Z","volume":10,"title":"GABAB receptor auxiliary subunits modulate Cav2.3-mediated release from medial habenula terminals","oa_version":"Published Version","author":[{"orcid":"0000-0003-0863-4481","first_name":"Pradeep","id":"45EDD1BC-F248-11E8-B48F-1D18A9856A87","full_name":"Bhandari, Pradeep","last_name":"Bhandari"},{"last_name":"Vandael","full_name":"Vandael, David H","id":"3AE48E0A-F248-11E8-B48F-1D18A9856A87","first_name":"David H","orcid":"0000-0001-7577-1676"},{"full_name":"Fernández-Fernández, Diego","last_name":"Fernández-Fernández","first_name":"Diego"},{"first_name":"Thorsten","last_name":"Fritzius","full_name":"Fritzius, Thorsten"},{"first_name":"David","last_name":"Kleindienst","full_name":"Kleindienst, David","id":"42E121A4-F248-11E8-B48F-1D18A9856A87"},{"last_name":"Önal","id":"4659D740-F248-11E8-B48F-1D18A9856A87","full_name":"Önal, Hüseyin C","first_name":"Hüseyin C","orcid":"0000-0002-2771-2011"},{"first_name":"Jacqueline-Claire","id":"3786AB44-F248-11E8-B48F-1D18A9856A87","full_name":"Montanaro-Punzengruber, Jacqueline-Claire","last_name":"Montanaro-Punzengruber"},{"first_name":"Martin","full_name":"Gassmann, Martin","last_name":"Gassmann"},{"first_name":"Peter M","orcid":"0000-0001-5001-4804","full_name":"Jonas, Peter M","id":"353C1B58-F248-11E8-B48F-1D18A9856A87","last_name":"Jonas"},{"first_name":"Akos","last_name":"Kulik","full_name":"Kulik, Akos"},{"full_name":"Bettler, Bernhard","last_name":"Bettler","first_name":"Bernhard"},{"orcid":"0000-0001-8761-9444","first_name":"Ryuichi","full_name":"Shigemoto, Ryuichi","id":"499F3ABC-F248-11E8-B48F-1D18A9856A87","last_name":"Shigemoto"},{"full_name":"Koppensteiner, Peter","id":"3B8B25A8-F248-11E8-B48F-1D18A9856A87","last_name":"Koppensteiner","orcid":"0000-0002-3509-1948","first_name":"Peter"}],"day":"29","scopus_import":"1","user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","citation":{"ama":"Bhandari P, Vandael DH, Fernández-Fernández D, et al. GABAB receptor auxiliary subunits modulate Cav2.3-mediated release from medial habenula terminals. <i>eLife</i>. 2021;10. doi:<a href=\"https://doi.org/10.7554/ELIFE.68274\">10.7554/ELIFE.68274</a>","ieee":"P. Bhandari <i>et al.</i>, “GABAB receptor auxiliary subunits modulate Cav2.3-mediated release from medial habenula terminals,” <i>eLife</i>, vol. 10. eLife Sciences Publications, 2021.","short":"P. Bhandari, D.H. Vandael, D. Fernández-Fernández, T. Fritzius, D. Kleindienst, H.C. Önal, J.-C. Montanaro-Punzengruber, M. Gassmann, P.M. Jonas, A. Kulik, B. Bettler, R. Shigemoto, P. Koppensteiner, ELife 10 (2021).","chicago":"Bhandari, Pradeep, David H Vandael, Diego Fernández-Fernández, Thorsten Fritzius, David Kleindienst, Hüseyin C Önal, Jacqueline-Claire Montanaro-Punzengruber, et al. “GABAB Receptor Auxiliary Subunits Modulate Cav2.3-Mediated Release from Medial Habenula Terminals.” <i>ELife</i>. eLife Sciences Publications, 2021. <a href=\"https://doi.org/10.7554/ELIFE.68274\">https://doi.org/10.7554/ELIFE.68274</a>.","ista":"Bhandari P, Vandael DH, Fernández-Fernández D, Fritzius T, Kleindienst D, Önal HC, Montanaro-Punzengruber J-C, Gassmann M, Jonas PM, Kulik A, Bettler B, Shigemoto R, Koppensteiner P. 2021. GABAB receptor auxiliary subunits modulate Cav2.3-mediated release from medial habenula terminals. eLife. 10, e68274.","apa":"Bhandari, P., Vandael, D. H., Fernández-Fernández, D., Fritzius, T., Kleindienst, D., Önal, H. C., … Koppensteiner, P. (2021). GABAB receptor auxiliary subunits modulate Cav2.3-mediated release from medial habenula terminals. <i>ELife</i>. eLife Sciences Publications. <a href=\"https://doi.org/10.7554/ELIFE.68274\">https://doi.org/10.7554/ELIFE.68274</a>","mla":"Bhandari, Pradeep, et al. “GABAB Receptor Auxiliary Subunits Modulate Cav2.3-Mediated Release from Medial Habenula Terminals.” <i>ELife</i>, vol. 10, e68274, eLife Sciences Publications, 2021, doi:<a href=\"https://doi.org/10.7554/ELIFE.68274\">10.7554/ELIFE.68274</a>."},"language":[{"iso":"eng"}],"oa":1,"file":[{"checksum":"6ebcb79999f889766f7cd79ee134ad28","relation":"main_file","content_type":"application/pdf","access_level":"open_access","file_name":"2021_eLife_Bhandari.pdf","success":1,"file_id":"9440","creator":"cziletti","date_updated":"2021-05-31T09:43:09Z","file_size":8174719,"date_created":"2021-05-31T09:43:09Z"}],"article_number":"e68274","department":[{"_id":"RySh"},{"_id":"PeJo"}],"month":"04","quality_controlled":"1","ddc":["570"],"type":"journal_article","date_updated":"2024-03-25T23:30:16Z","_id":"9437","publisher":"eLife Sciences Publications","doi":"10.7554/ELIFE.68274","article_processing_charge":"No","acknowledgement":"We are grateful to Akari Hagiwara and Toshihisa Ohtsuka for CAST antibody, and Masahiko Watanabe for neurexin antibody. We thank David Adams for kindly providing the stable Cav2.3 cell line. Cav2.3 KO mice were kindly provided by Tsutomu Tanabe. This project has received funding from the European Research Council (ERC) and European Commission (EC), under the European Union’s Horizon 2020 research and innovation programme (ERC grant agreement no. 694539 to Ryuichi Shigemoto, no. 692692 to Peter Jonas, and the Marie Skłodowska-Curie grant agreement no. 665385 to Cihan Önal), the Swiss National Science Foundation Grant 31003A-172881 to Bernhard Bettler and Deutsche Forschungsgemeinschaft (For 2143) and BIOSS-2 to Akos Kulik.","date_published":"2021-04-29T00:00:00Z","ec_funded":1,"project":[{"grant_number":"694539","name":"In situ analysis of single channel subunit composition in neurons: physiological implication in synaptic plasticity and behaviour","call_identifier":"H2020","_id":"25CA28EA-B435-11E9-9278-68D0E5697425"},{"call_identifier":"H2020","grant_number":"692692","name":"Biophysics and circuit function of a giant cortical glumatergic synapse","_id":"25B7EB9E-B435-11E9-9278-68D0E5697425"},{"call_identifier":"H2020","grant_number":"665385","name":"International IST Doctoral Program","_id":"2564DBCA-B435-11E9-9278-68D0E5697425"}],"publication":"eLife","status":"public","external_id":{"isi":["000651761700001"]},"related_material":{"link":[{"relation":"earlier_version","url":"https://doi.org/10.1101/2020.04.16.045112"}],"record":[{"id":"9562","relation":"dissertation_contains","status":"public"}]},"isi":1,"year":"2021"},{"doi":"10.3390/ijms21186737","article_processing_charge":"No","publisher":"MDPI","date_updated":"2024-03-25T23:30:16Z","_id":"8532","type":"journal_article","ddc":["570"],"quality_controlled":"1","year":"2020","isi":1,"external_id":{"isi":["000579945300001"]},"related_material":{"record":[{"id":"9562","relation":"dissertation_contains","status":"public"}]},"project":[{"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":"25CA28EA-B435-11E9-9278-68D0E5697425"},{"_id":"25D32BC0-B435-11E9-9278-68D0E5697425","name":"Mechanism of formation and maintenance of input side-dependent asymmetry in the hippocampus"},{"grant_number":"785907","name":"Human Brain Project Specific Grant Agreement 2 (HBP SGA 2)","call_identifier":"H2020","_id":"26436750-B435-11E9-9278-68D0E5697425"}],"publication":"International Journal of Molecular Sciences","status":"public","ec_funded":1,"date_published":"2020-09-14T00:00:00Z","acknowledgement":"This research was funded by Austrian Academy of Sciences, DOC fellowship to D.K., European Research\r\nCouncil Advanced Grant 694539 and European Union Human Brain Project (HBP) SGA2 785907 to R.S.\r\nWe acknowledge Elena Hollergschwandtner for technical support.","author":[{"first_name":"David","last_name":"Kleindienst","full_name":"Kleindienst, David","id":"42E121A4-F248-11E8-B48F-1D18A9856A87"},{"first_name":"Jacqueline-Claire","full_name":"Montanaro-Punzengruber, Jacqueline-Claire","id":"3786AB44-F248-11E8-B48F-1D18A9856A87","last_name":"Montanaro-Punzengruber"},{"last_name":"Bhandari","id":"45EDD1BC-F248-11E8-B48F-1D18A9856A87","full_name":"Bhandari, Pradeep","first_name":"Pradeep","orcid":"0000-0003-0863-4481"},{"last_name":"Case","id":"44B7CA5A-F248-11E8-B48F-1D18A9856A87","full_name":"Case, Matthew J","first_name":"Matthew J"},{"last_name":"Fukazawa","full_name":"Fukazawa, Yugo","first_name":"Yugo"},{"orcid":"0000-0001-8761-9444","first_name":"Ryuichi","last_name":"Shigemoto","id":"499F3ABC-F248-11E8-B48F-1D18A9856A87","full_name":"Shigemoto, Ryuichi"}],"day":"14","scopus_import":"1","oa_version":"Published Version","title":"Deep learning-assisted high-throughput analysis of freeze-fracture replica images applied to glutamate receptors and calcium channels at hippocampal synapses","volume":21,"article_type":"original","date_created":"2020-09-20T22:01:35Z","has_accepted_license":"1","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png","short":"CC BY (4.0)"},"intvolume":"        21","abstract":[{"lang":"eng","text":"The molecular anatomy of synapses defines their characteristics in transmission and plasticity. Precise measurements of the number and distribution of synaptic proteins are important for our understanding of synapse heterogeneity within and between brain regions. Freeze–fracture replica immunogold electron microscopy enables us to analyze them quantitatively on a two-dimensional membrane surface. Here, we introduce Darea software, which utilizes deep learning for analysis of replica images and demonstrate its usefulness for quick measurements of the pre- and postsynaptic areas, density and distribution of gold particles at synapses in a reproducible manner. We used Darea for comparing glutamate receptor and calcium channel distributions between hippocampal CA3-CA1 spine synapses on apical and basal dendrites, which differ in signaling pathways involved in synaptic plasticity. We found that apical synapses express a higher density of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and a stronger increase of AMPA receptors with synaptic size, while basal synapses show a larger increase in N-methyl-D-aspartate (NMDA) receptors with size. Interestingly, AMPA and NMDA receptors are segregated within postsynaptic sites and negatively correlated in density among both apical and basal synapses. In the presynaptic sites, Cav2.1 voltage-gated calcium channels show similar densities in apical and basal synapses with distributions consistent with an exclusion zone model of calcium channel-release site topography."}],"publication_status":"published","publication_identifier":{"eissn":["14220067"],"issn":["16616596"]},"file_date_updated":"2020-09-21T14:08:58Z","month":"09","department":[{"_id":"RySh"}],"article_number":"6737","file":[{"content_type":"application/pdf","access_level":"open_access","file_name":"2020_JournMolecSciences_Kleindienst.pdf","success":1,"checksum":"2e4f62f3cfe945b7391fc3070e5a289f","relation":"main_file","date_updated":"2020-09-21T14:08:58Z","creator":"dernst","file_size":5748456,"date_created":"2020-09-21T14:08:58Z","file_id":"8551"}],"oa":1,"language":[{"iso":"eng"}],"issue":"18","citation":{"ama":"Kleindienst D, Montanaro-Punzengruber J-C, Bhandari P, Case MJ, Fukazawa Y, Shigemoto R. Deep learning-assisted high-throughput analysis of freeze-fracture replica images applied to glutamate receptors and calcium channels at hippocampal synapses. <i>International Journal of Molecular Sciences</i>. 2020;21(18). doi:<a href=\"https://doi.org/10.3390/ijms21186737\">10.3390/ijms21186737</a>","ieee":"D. Kleindienst, J.-C. Montanaro-Punzengruber, P. Bhandari, M. J. Case, Y. Fukazawa, and R. Shigemoto, “Deep learning-assisted high-throughput analysis of freeze-fracture replica images applied to glutamate receptors and calcium channels at hippocampal synapses,” <i>International Journal of Molecular Sciences</i>, vol. 21, no. 18. MDPI, 2020.","short":"D. Kleindienst, J.-C. Montanaro-Punzengruber, P. Bhandari, M.J. Case, Y. Fukazawa, R. Shigemoto, International Journal of Molecular Sciences 21 (2020).","ista":"Kleindienst D, Montanaro-Punzengruber J-C, Bhandari P, Case MJ, Fukazawa Y, Shigemoto R. 2020. Deep learning-assisted high-throughput analysis of freeze-fracture replica images applied to glutamate receptors and calcium channels at hippocampal synapses. International Journal of Molecular Sciences. 21(18), 6737.","chicago":"Kleindienst, David, Jacqueline-Claire Montanaro-Punzengruber, Pradeep Bhandari, Matthew J Case, Yugo Fukazawa, and Ryuichi Shigemoto. “Deep Learning-Assisted High-Throughput Analysis of Freeze-Fracture Replica Images Applied to Glutamate Receptors and Calcium Channels at Hippocampal Synapses.” <i>International Journal of Molecular Sciences</i>. MDPI, 2020. <a href=\"https://doi.org/10.3390/ijms21186737\">https://doi.org/10.3390/ijms21186737</a>.","apa":"Kleindienst, D., Montanaro-Punzengruber, J.-C., Bhandari, P., Case, M. J., Fukazawa, Y., &#38; Shigemoto, R. (2020). Deep learning-assisted high-throughput analysis of freeze-fracture replica images applied to glutamate receptors and calcium channels at hippocampal synapses. <i>International Journal of Molecular Sciences</i>. MDPI. <a href=\"https://doi.org/10.3390/ijms21186737\">https://doi.org/10.3390/ijms21186737</a>","mla":"Kleindienst, David, et al. “Deep Learning-Assisted High-Throughput Analysis of Freeze-Fracture Replica Images Applied to Glutamate Receptors and Calcium Channels at Hippocampal Synapses.” <i>International Journal of Molecular Sciences</i>, vol. 21, no. 18, 6737, MDPI, 2020, doi:<a href=\"https://doi.org/10.3390/ijms21186737\">10.3390/ijms21186737</a>."},"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8"},{"publication_status":"published","publication_identifier":{"issn":["2663-337X"]},"file_date_updated":"2021-03-01T23:30:04Z","abstract":[{"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","lang":"eng"}],"acknowledged_ssus":[{"_id":"EM-Fac"}],"has_accepted_license":"1","date_created":"2020-02-26T10:56:37Z","oa_version":"Published Version","title":"Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway","author":[{"id":"45EDD1BC-F248-11E8-B48F-1D18A9856A87","full_name":"Bhandari, Pradeep","last_name":"Bhandari","first_name":"Pradeep","orcid":"0000-0003-0863-4481"}],"day":"28","user_id":"c635000d-4b10-11ee-a964-aac5a93f6ac1","citation":{"mla":"Bhandari, Pradeep. <i>Localization and Functional Role of Cav2.3 in the Medial Habenula to Interpeduncular Nucleus Pathway</i>. Institute of Science and Technology Austria, 2020, doi:<a href=\"https://doi.org/10.15479/AT:ISTA:7525\">10.15479/AT:ISTA:7525</a>.","apa":"Bhandari, P. (2020). <i>Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/AT:ISTA:7525\">https://doi.org/10.15479/AT:ISTA:7525</a>","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. <a href=\"https://doi.org/10.15479/AT:ISTA:7525\">https://doi.org/10.15479/AT:ISTA:7525</a>.","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.","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.","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.","ama":"Bhandari P. Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway. 2020. doi:<a href=\"https://doi.org/10.15479/AT:ISTA:7525\">10.15479/AT:ISTA:7525</a>"},"language":[{"iso":"eng"}],"oa":1,"file":[{"title":"Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway","file_id":"7538","date_created":"2020-02-28T08:37:53Z","file_size":9646346,"date_updated":"2021-03-01T23:30:04Z","creator":"pbhandari","embargo":"2021-02-28","relation":"main_file","checksum":"4589234fdb12b4ad72273b311723a7b4","file_name":"Pradeep Bhandari Thesis.pdf","content_type":"application/pdf","access_level":"open_access"},{"embargo_to":"open_access","title":"Localization and functional role of Cav2.3 in the medial habenula to interpeduncular nucleus pathway","file_id":"7539","creator":"pbhandari","date_updated":"2021-03-01T23:30:04Z","date_created":"2020-02-28T08:47:14Z","file_size":35252164,"checksum":"aa79490553ca0a5c9b6fbcd152e93928","relation":"source_file","content_type":"application/vnd.openxmlformats-officedocument.wordprocessingml.document","access_level":"closed","file_name":"Pradeep Bhandari Thesis.docx"}],"department":[{"_id":"RySh"}],"month":"02","supervisor":[{"first_name":"Ryuichi","orcid":"0000-0001-8761-9444","full_name":"Shigemoto, Ryuichi","id":"499F3ABC-F248-11E8-B48F-1D18A9856A87","last_name":"Shigemoto"}],"ddc":["570"],"page":"79","type":"dissertation","date_updated":"2023-09-07T13:20:03Z","_id":"7525","publisher":"Institute of Science and Technology Austria","doi":"10.15479/AT:ISTA:7525","article_processing_charge":"No","alternative_title":["ISTA Thesis"],"date_published":"2020-02-28T00:00:00Z","status":"public","degree_awarded":"PhD","keyword":["Cav2.3","medial habenula (MHb)","interpeduncular nucleus (IPN)"],"year":"2020"}]