Soykan, Tolga

[["dc.bibliographiccitation.firstpage","628"],["dc.bibliographiccitation.issue","5"],["dc.bibliographiccitation.journal","Neuron"],["dc.bibliographiccitation.lastpage","642"],["dc.bibliographiccitation.volume","63"],["dc.contributor.author","Poulopoulos, Alexandros"],["dc.contributor.author","Aramuni, Gayane"],["dc.contributor.author","Meyer, Guido"],["dc.contributor.author","Soykan, Tolga"],["dc.contributor.author","Hoon, Mrinalini"],["dc.contributor.author","Papadopoulos, Theofilos"],["dc.contributor.author","Zhang, Mingyue"],["dc.contributor.author","Paarmann, Ingo"],["dc.contributor.author","Fuchs, Celine"],["dc.contributor.author","Harvey, Kirsten"],["dc.contributor.author","Jedlicka, Peter"],["dc.contributor.author","Schwarzacher, Stephan W."],["dc.contributor.author","Betz, Heinrich"],["dc.contributor.author","Harvey, Robert J."],["dc.contributor.author","Brose, Nils"],["dc.contributor.author","Zhang, Weiqi"],["dc.contributor.author","Varoqueaux, Frederique"],["dc.date.accessioned","2017-09-07T11:46:51Z"],["dc.date.available","2017-09-07T11:46:51Z"],["dc.date.issued","2009"],["dc.description.abstract","In the mammalian CNS, each neuron typically receives thousands of synaptic inputs from diverse classes of neurons. Synaptic transmission to the postsynaptic neuron relies on localized and transmitter-specific differentiation of the plasma membrane with postsynaptic receptor, scaffolding, and adhesion proteins accumulating in precise apposition to presynaptic sites of transmitter release. We identified protein interactions of the synaptic adhesion molecule neuroligin 2 that drive postsynaptic differentiation at inhibitory synapses. Neuroligin 2 binds the scaffolding protein gephyrin through a conserved cytoplasmic motif and functions as a specific activator of collybistin, thus guiding membrane tethering of the inhibitory postsynaptic scaffold. Complexes of neuroligin 2, gephyrin and collybistin are sufficient for cell-autonomous clustering of inhibitory neurotransmitter receptors. Deletion of neuroligin 2 in mice perturbs GABAergic and glycinergic synaptic transmission and leads to a loss of postsynaptic specializations specifically at perisomatic inhibitory synapses."],["dc.identifier.doi","10.1016/j.neuron.2009.08.023"],["dc.identifier.gro","3143057"],["dc.identifier.isi","000269852300010"],["dc.identifier.pmid","19755106"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/529"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Cell Press"],["dc.relation.issn","0896-6273"],["dc.title","Neuroligin 2 Drives Postsynaptic Assembly at Perisomatic Inhibitory Synapses through Gephyrin and Collybistin"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.journal","European Biophysics Journal"],["dc.bibliographiccitation.volume","42"],["dc.contributor.author","Schatz, M."],["dc.contributor.author","Soykan, T."],["dc.contributor.author","Brose, Nils"],["dc.contributor.author","Steinem, Claudia"],["dc.date.accessioned","2018-11-07T09:22:34Z"],["dc.date.available","2018-11-07T09:22:34Z"],["dc.date.issued","2013"],["dc.format.extent","S155"],["dc.identifier.isi","000330215300463"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/29375"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.publisher.place","New york"],["dc.relation.eventlocation","Lisbon, Portugal"],["dc.relation.issn","1432-1017"],["dc.relation.issn","0175-7571"],["dc.title","Lipid binding characteristics of collybistin"],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","321"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Biochemical Journal"],["dc.bibliographiccitation.lastpage","330"],["dc.bibliographiccitation.volume","446"],["dc.contributor.author","Poulopoulos, Alexandros"],["dc.contributor.author","Soykan, Tolga"],["dc.contributor.author","Tuffy, Liam P."],["dc.contributor.author","Hammer, Matthieu"],["dc.contributor.author","Varoqueaux, Frédérique"],["dc.contributor.author","Brose, Nils"],["dc.date.accessioned","2017-09-07T11:48:25Z"],["dc.date.available","2017-09-07T11:48:25Z"],["dc.date.issued","2012"],["dc.description.abstract","Neuroligins are postsynaptic adhesion proteins involved in the establishment of functional synapses in the central nervous system. In rodents, four genes give rise to neuroligins that function at distinct synapses, with corresponding neurotransmitter and subtype specificities. In the present study, we examined the interactions between the different neuroligins by isolating endogenous oligomeric complexes using in situ cross-linking on primary neurons. Examining hippocampal, striatal, cerebellar and spinal cord cultures, we found that neuroligins form constitutive dimers, including homomers and, most notably, neuroligin 1/3 heteromers. Additionally, we found that neuroligin monomers are specifically retained in the secretory pathway through a cellular quality control mechanism that involves the neuroligin transmembrane domain, ensuring that dimerization occurs prior to cell surface trafficking. Lastly, we identified differences in the dimerization capacity of autism-associated neuroligin mutants, and found that neuroligin 3 R471C mutants can form heterodimers with neuroligin 1. The pervasive nature of neuroligin dimerization indicates that the unit of neuroligin function is the dimer, and raises intriguing possibilities of distinct heterodimer functions, and of interactions between native and mutant neuroligins contributing to disease phenotypes."],["dc.identifier.doi","10.1042/BJ20120808"],["dc.identifier.gro","3142468"],["dc.identifier.isi","000308767500016"],["dc.identifier.pmid","22671294"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/8618"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0264-6021"],["dc.title","Homodimerization and isoform-specific heterodimerization of neuroligins"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2113"],["dc.bibliographiccitation.issue","18"],["dc.bibliographiccitation.journal","EMBO Journal"],["dc.bibliographiccitation.lastpage","2133"],["dc.bibliographiccitation.volume","33"],["dc.contributor.author","Soykan, Tolga"],["dc.contributor.author","Schneeberger, Daniela"],["dc.contributor.author","Tria, Giancarlo"],["dc.contributor.author","Buechner, Claudia"],["dc.contributor.author","Bader, Nicole"],["dc.contributor.author","Svergun, Dmitri"],["dc.contributor.author","Tessmer, Ingrid"],["dc.contributor.author","Poulopoulos, Alexandros"],["dc.contributor.author","Papadopoulos, Theofilos"],["dc.contributor.author","Varoqueaux, Frédérique"],["dc.contributor.author","Schindelin, Hermann"],["dc.contributor.author","Brose, Nils"],["dc.date.accessioned","2017-09-07T11:45:30Z"],["dc.date.available","2017-09-07T11:45:30Z"],["dc.date.issued","2014"],["dc.description.abstract","The formation of neuronal synapses and the dynamic regulation of their efficacy depend on the assembly of the postsynaptic neuro transmitter receptor apparatus. Receptor recruitment to inhibitory GABAergic and glycinergic synapses is controlled by the scaffold protein gephyrin and the adaptor protein collybistin. We derived new insights into the structure of collybistin and used these to design biochemical, cell biological, and genetic analyses of collybistin function. Our data define a collybistin-based protein interaction network that controls the gephyrin content of inhibitory postsynapses. Within this network, collybistin can adopt open/active and closed/inactive conformations to act as a switchable adaptor that links gephyrin to plasma membrane phosphoinositides. This function of collybistin is regulated by binding of the adhesion protein neuroligin-2, which stabilizes the open/active conformation of collybistin at the postsynaptic plasma membrane by competing with an intramolecular interaction in collybistin that favors the closed/inactive conformation. By linking trans-synaptic neuroligin-dependent adhesion and phosphoinositide signaling with gephyrin recruitment, the collybistin-based regulatory switch mechanism represents an integrating regulatory node in the formation and function of inhibitory postsynapses."],["dc.identifier.doi","10.15252/embj.201488143"],["dc.identifier.gro","3142051"],["dc.identifier.isi","000342503000012"],["dc.identifier.pmid","25082542"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/4000"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.eissn","1460-2075"],["dc.relation.issn","0261-4189"],["dc.title","A conformational switch in collybistin determines the differentiation of inhibitory postsynapses"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3053"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","Proceedings of the National Academy of Sciences"],["dc.bibliographiccitation.lastpage","3058"],["dc.bibliographiccitation.volume","108"],["dc.contributor.author","Hoon, Mrinalini"],["dc.contributor.author","Soykan, Tolga"],["dc.contributor.author","Falkenburger, Björn"],["dc.contributor.author","Hammer, Matthieu"],["dc.contributor.author","Patrizi, Annarita"],["dc.contributor.author","Schmidt, Karl-Friedrich"],["dc.contributor.author","Sassoè-Pognetto, Marco"],["dc.contributor.author","Löwel, Siegrid"],["dc.contributor.author","Moser, Tobias"],["dc.contributor.author","Taschenberger, Holger"],["dc.contributor.author","Brose, Nils"],["dc.contributor.author","Varoqueaux, Frédérique"],["dc.date.accessioned","2017-09-07T11:44:21Z"],["dc.date.available","2017-09-07T11:44:21Z"],["dc.date.issued","2011"],["dc.description.abstract","Neuroligins (NL1-NL4) are postsynaptic adhesion proteins that control the maturation and function of synapses in the central nervous system (CNS). Loss-of-function mutations in NL4 are linked to rare forms of monogenic heritable autism, but its localization and function are unknown. Using the retina as a model system, we show that NL4 is preferentially localized to glycinergic postsynapses and that the loss of NL4 is accompanied by a reduced number of glycine receptors mediating fast glycinergic transmission. Accordingly, NL4-deficient ganglion cells exhibit slower glycinergic miniature postsynaptic currents and subtle alterations in their stimuluscoding efficacy, and inhibition within the NL4-deficient retinal network is altered as assessed by electroretinogram recordings. These data indicate that NL4 shapes network activity and information processing in the retina by modulating glycinergic inhibition. Importantly, NL4 is also targeted to inhibitory synapses in other areas of the CNS, such as the thalamus, colliculi, brainstem, and spinal cord, and forms complexes with the inhibitory postsynapse proteins gephyrin and collybistin in vivo, indicating that NL4 is an important component of glycinergic postsynapses."],["dc.identifier.doi","10.1073/pnas.1006946108"],["dc.identifier.gro","3142775"],["dc.identifier.isi","000287377000078"],["dc.identifier.pmid","21282647"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/216"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0027-8424"],["dc.title","Neuroligin-4 is localized to glycinergic postsynapses and regulates inhibition in the retina"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","20795"],["dc.bibliographiccitation.issue","51"],["dc.bibliographiccitation.journal","Proceedings of the National Academy of Sciences"],["dc.bibliographiccitation.lastpage","20800"],["dc.bibliographiccitation.volume","110"],["dc.contributor.author","Mayer, Simone"],["dc.contributor.author","Kumar, Rohit"],["dc.contributor.author","Jaiswal, Mamta"],["dc.contributor.author","Soykan, Tolga"],["dc.contributor.author","Ahmadian, Mohammad Reza"],["dc.contributor.author","Brose, Nils"],["dc.contributor.author","Betz, Heinrich"],["dc.contributor.author","Rhee, Jeong-Seop"],["dc.contributor.author","Papadopoulos, Theofilos"],["dc.date.accessioned","2017-09-07T11:46:59Z"],["dc.date.available","2017-09-07T11:46:59Z"],["dc.date.issued","2013"],["dc.description.abstract","In many brain regions, gephyrin and GABA(A) receptor clustering at developing inhibitory synapses depends on the guanine nucleotide exchange factor collybistin (Cb). The vast majority of Cb splice variants contain an autoinhibitory src homology 3 domain, and several synaptic proteins are known to bind to this SH3 domain and to thereby activate gephyrin clustering. However, many functional GABAergic synapses form independently of the known Cb-activating proteins, indicating that additional Cb activators must exist. Here we show that the small Rho-like GTPase TC10 stimulates Cb-dependent gephyrin clustering by binding in its active, GTP-bound state to the pleckstrin homology domain of Cb. Overexpression of a constitutively active TC10 variant in neurons causes an increase in the density of synaptic gephyrin clusters and mean miniature inhibitory postsynaptic current amplitudes, whereas a dominant negative TC10 variant has opposite effects. The enhancement of Cb-induced gephyrin clustering by GTP-TC10 does not depend on the guanine nucleotide exchange activity of Cb but involves an interaction that resembles reported interactions of other small GTPases with their effectors. Our data indicate that GTP-TC10 activates the major src homology 3 domain-containing Cb variants by relieving autoinhibition and thus define an alternative GTPase-driven signaling pathway in the genesis of inhibitory synapses."],["dc.identifier.doi","10.1073/pnas.1309078110"],["dc.identifier.gro","3142233"],["dc.identifier.isi","000328548600093"],["dc.identifier.pmid","24297911"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/6010"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Natl Acad Sciences"],["dc.relation.issn","0027-8424"],["dc.title","Collybistin activation by GTP-TC10 enhances postsynaptic gephyrin clustering and hippocampal GABAergic neurotransmission"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","244"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Journal of biological chemistry"],["dc.bibliographiccitation.lastpage","254"],["dc.bibliographiccitation.volume","291"],["dc.contributor.author","Ludolphs, Michaela"],["dc.contributor.author","Schneeberger, Daniela"],["dc.contributor.author","Soykan, Tolga"],["dc.contributor.author","Schäfer, Jonas"],["dc.contributor.author","Papadopoulos, Theofilos"],["dc.contributor.author","Brose, Nils"],["dc.contributor.author","Schindelin, Hermann"],["dc.contributor.author","Steinem, Claudia"],["dc.date.accessioned","2017-09-07T11:54:46Z"],["dc.date.available","2017-09-07T11:54:46Z"],["dc.date.issued","2016"],["dc.description.abstract","The regulatory protein collybistin (CB) recruits the receptor-scaffolding protein gephyrin to mammalian inhibitory glycinergic and GABAergic postsynaptic membranes in nerve cells. CB is tethered to the membrane via phosphoinositides. We developed an in vitro assay based on solid-supported 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine membranes doped with different phosphoinositides on silicon/silicon dioxide substrates to quantify the binding of various CB2 constructs using reflectometric interference spectroscopy. Based on adsorption isotherms, we obtained dissociation constants and binding capacities of the membranes. Our results show that full-length CB2 harboring the N-terminal Src homology 3 (SH3) domain (CB2(SH3+)) adopts a closed and autoinhibited conformation that largely prevents membrane binding. This autoinhibition is relieved upon introduction of the W24A/E262A mutation, which conformationally opens CB2(SH3+) and allows the pleckstrin homology domain to properly bind lipids depending on the phosphoinositide species with a preference for phosphatidylinositol 3-monophosphate and phosphatidylinositol 4-monophosphate. This type of membrane tethering under the control of the release of the SH3 domain of CB is essential for regulating gephyrin clustering."],["dc.identifier.doi","10.1074/jbc.M115.673400"],["dc.identifier.gro","3141755"],["dc.identifier.isi","000367589500019"],["dc.identifier.pmid","26546675"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/713"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.eissn","1083-351X"],["dc.relation.issn","0021-9258"],["dc.title","Specificity of Collybistin-Phosphoinositide Interactions"],["dc.title.subtitle","Impact of the individual Protein Domains"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]