Jungyong Nam

Korea Advanced Institute of Science and Technology

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Eunjoon Kim

Korea Advanced Institute of Science and Technology

Jaewon Ko

Daegu Gyeongbuk Institute of Science and Technology

Won Mah

Kyungpook National University

Hyun Kim

Korea University

Doyoun Kim

Korea Research Institute of Chemical Technology

Ji Won Um

Daegu Gyeongbuk Institute of Science and Technology

Ho Min Kim

Institute for Basic Science

Yan Li

McLean Hospital

Yong Chul Bae

Kyungpook National University

Yeong Shin Yim

Translational Therapeutics (United States)

Cooperative Institutions

Korea Advanced Institute of Science and Technology

Yonsei University

Institute for Basic Science

Seoul National University

Howard Hughes Medical Institute

Daegu Gyeongbuk Institute of Science and Technology

Korea University

Seoul National University Hospital

Kyungpook National University

Pohang University of Science and Technology

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

SALM4 suppresses excitatory synapse development by cis-inhibiting trans-synaptic SALM3–LAR adhesion

Nature Communications (2016)

Eunkyung Lie Ji Seung Ko Su‐Yeon Choi Junyeop Daniel Roh Yi Sul Cho

Abstract Synaptic adhesion molecules regulate various aspects of synapse development, function and plasticity. These functions mainly involve trans -synaptic interactions and positive regulations, whereas cis -interactions and negative regulation are less understood. Here we report that SALM4, a member of the SALM/Lrfn family of synaptic adhesion molecules, suppresses excitatory synapse development through cis inhibition of SALM3, another SALM family protein with synaptogenic activity. Salm4 -mutant ( Salm4 −/− ) mice show increased excitatory synapse numbers in the hippocampus. SALM4 cis -interacts with SALM3, inhibits trans -synaptic SALM3 interaction with presynaptic LAR family receptor tyrosine phosphatases and suppresses SALM3-dependent presynaptic differentiation. Importantly, deletion of Salm3 in Salm4 −/− mice ( Salm3 −/− ; Salm4 −/− ) normalizes the increased excitatory synapse number. These results suggest that SALM4 negatively regulates excitatory synapses via cis inhibition of the trans -synaptic SALM3–LAR adhesion.

Excitatory synapse

10.1038/ncomms12328

Cite

Citations (31)

Slitrks control excitatory and inhibitory synapse formation with LAR receptor protein tyrosine phosphatases

Yeong Shin Yim Younghee Kwon Jungyong Nam Hong In Yoon Kangduk Lee

The balance between excitatory and inhibitory synaptic inputs, which is governed by multiple synapse organizers, controls neural circuit functions and behaviors. Slit- and Trk-like proteins (Slitrks) are a family of synapse organizers, whose emerging synaptic roles are incompletely understood. Here, we report that Slitrks are enriched in postsynaptic densities in rat brains. Overexpression of Slitrks promoted synapse formation, whereas RNAi-mediated knockdown of Slitrks decreased synapse density. Intriguingly, Slitrks were required for both excitatory and inhibitory synapse formation in an isoform-dependent manner. Moreover, Slitrks required distinct members of the leukocyte antigen-related receptor protein tyrosine phosphatase (LAR-RPTP) family to trigger synapse formation. Protein tyrosine phosphatase σ (PTPσ), in particular, was specifically required for excitatory synaptic differentiation by Slitrks, whereas PTPδ was necessary for inhibitory synapse differentiation. Taken together, these data suggest that combinatorial interactions of Slitrks with LAR-RPTP family members maintain synapse formation to coordinate excitatory–inhibitory balance.

Excitatory synapse

Source

Cite

Citations (0)

Regulation of Dendritic Spines, Spatial Memory, and Embryonic Development by the TANC Family of PSD-95-Interacting Proteins

Journal of Neuroscience (2010)

Seungnam Han Jungyong Nam Yan Li Se-Ho Kim Suk-Hee Cho

PSD-95 (postsynaptic density-95) is thought to play important roles in the regulation of dendritic spines and excitatory synapses, but the underlying mechanisms have not been fully elucidated. TANC1 is a PSD-95-interacting synaptic protein that contains multiple domains for protein-protein interactions but whose function is not well understood. In the present study, we provide evidence that TANC1 and its close relative TANC2 regulate dendritic spines and excitatory synapses. Overexpression of TANC1 and TANC2 in cultured neurons increases the density of dendritic spines and excitatory synapses in a manner that requires the PDZ (PSD-95/Dlg/ZO-1)-binding C termini of TANC proteins. TANC1-deficient mice exhibit reduced spine density in the CA3 region of the hippocampus, but not in the CA1 or dentate gyrus regions, and show impaired spatial memory. TANC2 deficiency, however, causes embryonic lethality. These results suggest that TANC1 is important for dendritic spine maintenance and spatial memory, and implicate TANC2 in embryonic development.

Postsynaptic density

PDZ domain

Dendritic filopodia

10.1523/jneurosci.3128-10.2010

Cite

Citations (68)

The adhesion protein IgSF9b is coupled to neuroligin 2 via S-SCAM to promote inhibitory synapse development

The Journal of Cell Biology (2013)

Jooyeon Woo Seok‐Kyu Kwon Jungyong Nam Seungwon Choi Hideto Takahashi

Synaptic adhesion molecules regulate diverse aspects of synapse formation and maintenance. Many known synaptic adhesion molecules localize at excitatory synapses, whereas relatively little is known about inhibitory synaptic adhesion molecules. Here we report that IgSF9b is a novel, brain-specific, homophilic adhesion molecule that is strongly expressed in GABAergic interneurons. IgSF9b was preferentially localized at inhibitory synapses in cultured rat hippocampal and cortical interneurons and was required for the development of inhibitory synapses onto interneurons. IgSF9b formed a subsynaptic domain distinct from the GABAA receptor– and gephyrin-containing domain, as indicated by super-resolution imaging. IgSF9b was linked to neuroligin 2, an inhibitory synaptic adhesion molecule coupled to gephyrin, via the multi-PDZ protein S-SCAM. IgSF9b and neuroligin 2 could reciprocally cluster each other. These results suggest a novel mode of inhibitory synaptic organization in which two subsynaptic domains, one containing IgSF9b for synaptic adhesion and the other containing gephyrin and GABAA receptors for synaptic transmission, are interconnected through S-SCAM and neuroligin 2.

Gephyrin

Neuroligin

Neurexin

PDZ domain

10.1083/jcb.201209132

Cite

Citations (91)

Slitrks control excitatory and inhibitory synapse formation with LAR receptor protein tyrosine phosphatases

Proceedings of the National Academy of Sciences (2013)

Yeong Shin Yim Younghee Kwon Jungyong Nam Hong In Yoon Kangduk Lee

Excitatory synapse

Postsynaptic density

10.1073/pnas.1209881110

Cite

Citations (174)

The SALM/Lrfn family of leucine-rich repeat-containing cell adhesion molecules

Seminars in Cell and Developmental Biology (2011)

Jungyong Nam Won Mah Eunjoon Kim

Neurite

PDZ domain

Nectin

Postsynaptic density

Immunoglobulin superfamily

10.1016/j.semcdb.2011.06.005

Cite

Citations (70)

Selected SALM (Synaptic Adhesion-Like Molecule) Family Proteins Regulate Synapse Formation

Journal of Neuroscience (2010)

Won Mah Jaewon Ko Jungyong Nam Kihoon Han Woosuk Chung

Synaptic cell adhesion molecules regulate various steps of synapse formation. Despite the great diversity of neuronal synapses, relatively few adhesion molecules with synaptogenic activity have been identified. Synaptic adhesion-like molecules (SALMs) are members of a family of cell adhesion molecules known to regulate neurite outgrowth and synapse maturation; however, the role of SALMs in synapse formation remains unknown. We found that expression of the SALM family proteins SALM3 and SALM5 in nonneural and neural cells induces both excitatory and inhibitory presynaptic differentiation in contacting axons. SALM3 and SALM5 proteins are enriched in synaptic fractions, and form strong (SALM3) or weak (SALM5) complexes with postsynaptic density-95 (PSD-95), an abundant postsynaptic scaffolding protein at excitatory synapses. Aggregation of SALM3, but not SALM5, on dendritic surfaces induces clustering of PSD-95. Knockdown of SALM5 reduces the number and function of excitatory and inhibitory synapses. These results suggest that selected SALM family proteins regulate synapse formation, and that SALM3 and SALM5 may promote synapse formation through distinct mechanisms.

Excitatory synapse

Postsynaptic density

Silent synapse

Neurite

10.1523/jneurosci.4839-09.2010

Cite

Citations (89)

Structural basis for LAR-RPTP/Slitrk complex-mediated synaptic adhesion

Nature Communications (2014)

Ji Won Um Kee Hun Kim Beom Seok Park Yeonsoo Choi Doyoun Kim

10.1038/ncomms6423

Cite

Citations (102)

SALM5 trans-synaptically interacts with LAR-RPTPs in a splicing-dependent manner to regulate synapse development

Scientific Reports (2016)

Yeonsoo Choi Jungyong Nam Daniel J. Whitcomb Yoo Sung Song Doyoun Kim

Abstract Synaptogenic adhesion molecules play critical roles in synapse formation. SALM5/Lrfn5, a SALM/Lrfn family adhesion molecule implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons, but its presynaptic ligand remains unknown. We found that SALM5 interacts with the Ig domains of LAR family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPδ, and PTPσ). These interactions are strongly inhibited by the splice insert B in the Ig domain region of LAR-RPTPs, and mediate SALM5-dependent presynaptic differentiation in contacting axons. In addition, SALM5 regulates AMPA receptor-mediated synaptic transmission through mechanisms involving the interaction of postsynaptic SALM5 with presynaptic LAR-RPTPs. These results suggest that postsynaptic SALM5 promotes synapse development by trans-synaptically interacting with presynaptic LAR-RPTPs and is important for the regulation of excitatory synaptic strength.

Excitatory synapse

Neurexin

Neuroligin

Silent synapse

10.1038/srep26676

Cite

Citations (66)