記述言語：英語   出版者・発行元：Frontiers in Molecular Neuroscience  

DOI： 10.3389/fnmol.2025.1564028

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Scopus

PubMed

記述言語：日本語   出版者・発行元：日本生物学的精神医学会  

脳内のシナプスは情報伝達の基盤であり，多様な高次脳機能の制御に不可欠な役割を担っている。複雑な脳機能の理解や精神・神経疾患の病態解明には，異なる脳領域に特異的なシナプスの構成タンパク質成分や分子メカニズムを同定することが重要である。しかし，従来の生化学的な解析手法では，生体脳から特定のシナプスを選択的に分離し，その詳細な分子情報を得ることは困難であった。このような背景のなか，近年，近位依存性ビオチン標識（BioID）法を応用した生体内BioID法が開発され，脳内の特定シナプスや細胞接着部位のプロテオームを高い空間解像度で網羅的に解析することが可能となっている。本稿では，進展を続けるBioID法による脳内のシナプスプロテオーム研究の最新成果を概説し，筆者らが新たに開発した生体内BioID技術を用いたアストロサイト‐神経細胞シナプス間の新規分子メカニズムの解明についても紹介する。

DOI： 10.11249/jsbpjjpp.36.2_80

CiNii Research

記述言語：英語  

DOI： 10.1101/2023.04.09.536178

PubMed

担当区分：責任著者   記述言語：英語   出版者・発行元：Nature Chemical Biology  

Identifying the protein component of calcium signaling in specific subcellular regions presents considerable challenges. Researchers have now successfully integrated calcium indicators with proximity labeling, enabling the targeting of microdomain-specific calcium signaling.

DOI： 10.1038/s41589-024-01656-8

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Scopus

PubMed

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Frontiers in Molecular Neuroscience  

Synapses play a pivotal role in forming neural circuits, with critical implications for brain functions such as learning, memory, and emotions. Several advances in synaptic research have demonstrated the diversity of synaptic structure and function, which can form thousands of connections depending on the neuronal cell types. Moreover, synapses not only interconnect neurons but also establish connections with glial cells such as astrocytes, which play a key role in the architecture and function of neuronal circuits in the brain. Emerging evidence suggests that dysfunction of synaptic proteins contributes to a variety of neurological and psychiatric disorders. Therefore, it is crucial to determine the molecular networks within synapses in various neuronal cell types to gain a deeper understanding of how the nervous system regulates brain function. Recent advances in synaptic proteome approaches, such as fluorescence-activated synaptosome sorting (FASS) and proximity labeling, have allowed for a detailed and spatial analysis of many cell-type-specific synaptic molecules in vivo. In this brief review, we highlight these novel spatial proteomic approaches and discuss the regulation of synaptic formation and function in the brain. This knowledge of molecular networks provides new insight into the understanding of many neurological and psychiatric disorders.

DOI： 10.3389/fnmol.2024.1361956

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Scopus

PubMed

担当区分：最終著者,　責任著者  

DOI： https://doi.org/10.1016/j.neures.2023.01.005

担当区分：最終著者,　責任著者   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/j.neures.2023.01.005

DOI： https://doi.org/10.1007/s11064-022-03623-y

掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media LLC  

DOI： 10.1007/s11064-022-03623-y

その他リンク： https://link.springer.com/article/10.1007/s11064-022-03623-y/fulltext.html

DOI： 10.1186/s12915-022-01312-4.

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

Lemur tail kinase 1 (LMTK1), previously called apoptosis-associated tyrosine kinase (AATYK), is an endosomal Ser/Thr kinase. We recently reported that LMTK1 regulates axon outgrowth, dendrite arborization and spine formation via Rab11-mediated vesicle transport. Rab11, a small GTPase regulating recycling endosome trafficking, is shown to be associated with late-onset Alzheimer's disease (LOAD). In fact, genome-wide association studies identified many proteins regulating vesicle transport as risk factors for LOAD. Furthermore, LMTK1 has been reported to be a risk factor for frontotemporal dementia. Then, we hypothesized that LMTK1 contributes to AD development through vesicle transport and examined the effect of LMTK1 on the cellular localization of AD-related proteins, amyloid precursor protein (APP) and β-site APP cleaving enzyme 1 (BACE1). The β-cleavage of APP by BACE1 is the initial and rate-limiting step in Aβ generation. We found that LMTK1 accumulated BACE1, but not APP, to the perinuclear endosomal compartment, whereas the kinase-negative (kn) mutant of LMTK1A did not. The β-C-terminal fragment was prone to increase under overexpression of LMTK1A kn. Moreover, the expression level of LMTK1A was reduced in AD brains. These results suggest the possibility that LMTK1 is involved in AD development through the regulation of the proper endosomal localization of BACE1.

DOI： 10.1093/jb/mvab094

PubMed

担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

The astrocyte is a central glial cell and plays a critical role in the architecture and activity of neuronal circuits and brain functions through forming a tripartite synapse with neurons. Emerging evidence suggests that dysfunction of tripartite synaptic connections contributes to a variety of psychiatric and neurodevelopmental disorders. Furthermore, recent advancements with transcriptome profiling, cell biological and physiological approaches have provided new insights into the molecular mechanisms into how astrocytes control synaptogenesis in the brain. In addition to these findings, we have recently developed in vivo cell-surface proximity-dependent biotinylation (BioID) approaches, TurboID-surface and Split-TurboID, to comprehensively understand the molecular composition between astrocytes and neuronal synapses. These proteomic approaches have discovered a novel molecular framework for understanding the tripartite synaptic cleft that arbitrates neuronal circuit formation and function. Here, this short review highlights novel in vivo cell-surface BioID approaches and recent advances in this rapidly evolving field, emphasizing how astrocytes regulate excitatory and inhibitory synapse formation in vitro and in vivo.

DOI： 10.1016/j.neures.2021.05.002

PubMed

担当区分：筆頭著者,　責任著者   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41586-020-2926-0

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Schizophrenia (SCZ) is known to be a heritable disorder; however, its multifactorial nature has significantly hampered attempts to establish its pathogenesis. Therefore, in this study, we performed genome-wide copy-number variation (CNV) analysis of 2940 patients with SCZ and 2402 control subjects and identified a statistically significant association between SCZ and exonic CNVs in the ARHGAP10 gene. ARHGAP10 encodes a member of the RhoGAP superfamily of proteins that is involved in small GTPase signaling. This signaling pathway is one of the SCZ-associated pathways and may contribute to neural development and function. However, the ARHGAP10 gene is often confused with ARHGAP21, thus, the significance of ARHGAP10 in the molecular pathology of SCZ, including the expression profile of the ARHGAP10 protein, remains poorly understood. To address this issue, we focused on one patient identified to have both an exonic deletion and a missense variant (p.S490P) in ARHGAP10. The missense variant was found to be located in the RhoGAP domain and was determined to be relevant to the association between ARHGAP10 and the active form of RhoA. We evaluated ARHGAP10 protein expression in the brains of reporter mice and generated a mouse model to mimic the patient case. The model exhibited abnormal emotional behaviors, along with reduced spine density in the medial prefrontal cortex (mPFC). In addition, primary cultured neurons prepared from the mouse model brain exhibited immature neurites in vitro. Furthermore, we established induced pluripotent stem cells (iPSCs) from this patient, and differentiated them into tyrosine hydroxylase (TH)-positive neurons in order to analyze their morphological phenotypes. TH-positive neurons differentiated from the patient-derived iPSCs exhibited severe defects in both neurite length and branch number; these defects were restored by the addition of the Rho-kinase inhibitor, Y-27632. Collectively, our findings suggest that rare ARHGAP10 variants may be genetically and biologically associated with SCZ and indicate that Rho signaling represents a promising drug discovery target for SCZ treatment.

DOI： 10.1038/s41398-020-00917-z

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Dopamine (DA) activates mitogen-activated protein kinase (MAPK) via protein kinase A (PKA)/Rap1 in medium spiny neurons (MSNs) expressing the dopamine D1 receptor (D1R) in the nucleus accumbens (NAc), thereby regulating reward-related behavior. However, how MAPK regulates reward-related learning and memory through gene expression is poorly understood. Here, to identify the relevant transcriptional factors, we perform proteomic analysis using affinity beads coated with cyclic AMP response element binding protein (CREB)-binding protein (CBP), a transcriptional coactivator involved in reward-related behavior. We identify more than 400 CBP-interacting proteins, including Neuronal Per Arnt Sim domain protein 4 (Npas4). We find that MAPK phosphorylates Npas4 downstream of PKA, increasing the Npas4-CBP interaction and the transcriptional activity of Npas4 at the brain-derived neurotrophic factor (BDNF) promoter. The deletion of Npas4 in D1R-expressing MSNs impairs cocaine-induced place preference, which is rescued by Npas4-wild-type (WT), but not by a phospho-deficient Npas4 mutant. These observations suggest that MAPK phosphorylates Npas4 in D1R-MSNs and increases transcriptional activity to enhance reward-related learning and memory.

DOI： 10.1016/j.celrep.2019.10.116

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Dendritic spines are postsynaptic protrusions at excitatory synapses that are critical for proper neuronal synaptic transmission. While lipid and protein membrane components are necessary for spine formation, it is largely unknown how they are recruited to developing spines. Endosomal trafficking is one mechanism that may influence this development. We recently reported that Lemur kinase 1A (LMTK1A), a membrane-bound Ser/Thr kinase, regulates trafficking of endosomes in neurons. LMTK1 has been shown to be a p35 Cdk5 activator-binding protein and a substrate for Cdk5-p35; however, its neuronal function has not been sufficiently studied. Here, we investigate the role of LMTK1 in spine formation. Depletion of LMTK1 increases spine formation, maturation, and density in primary cultured neurons and in mouse brain of either sex. Additionally, expression of kinase-negative LMTK1 stimulates spine formation in primary neurons and in vivo LMTK1 controls spine formation through Rab11, a regulator of recycling endosome trafficking. We identify TBC1D9B, a Rab11A GTPase-activating protein (Rab11A GAP), as a LMTK1 binding protein, and find that TBC1D9B mediates LMTK1 activity on Rab11A. TBC1D9B inactivates Rab11A under the control of LMTK1A. Further, by analyzing the effect of decreased TBC1D9B expression in primary neurons, we demonstrate that TBC1D9B indeed regulates spine formation. This is the first demonstration of the biological function of TBC1D9B. Together, with the regulation of LMTK1 by Cdk5-p35, we propose the Cdk5-LMTK1-TBC1D9B-Rab11A cascade as a novel signaling mechanism regulating endosomal transport for synapse formation and function.SIGNIFICANCE STATEMENT Dendritic spines are postsynaptic specializations essential for synaptic transmission. However, it is not known how critical membrane components are recruited to spines for their formation. Endosomal trafficking is one such mechanism that may mediate this process. Here we investigate regulators of endosomal trafficking and their contribution to spine formation. We identify two novel factors, LMTK1 and TBC1D9B, which regulate spine formation upstream of Rab11A, a small GTPase. LMTK1 is a membrane bound Ser/Thr kinase regulated by Cdk5-p35, and TBC1D9B is a recently identified Rab11 GAP. LMTK1 controls the GAP activity of TBC1D9B on Rab11A, and TBC1D9B mediates the LMTK1 activity on Rab11A. We propose the Cdk5-LMTK1-TBC1D9B-Rab11A cascade as a novel mechanism controlling spine formation and function.

DOI： 10.1523/JNEUROSCI.3209-18.2019

PubMed

担当区分：筆頭著者  

DOI： 10.3389/fcell.2019.00069

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41467-017-00044-2

Web of Science

PubMed

記述言語：英語  

記述言語：英語  

会議種別：公開講演，セミナー，チュートリアル，講習，講義等  

会議種別：シンポジウム・ワークショップ パネル（公募）  

会議種別：シンポジウム・ワークショップ パネル（公募）  

会議種別：公開講演，セミナー，チュートリアル，講習，講義等  

記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）  

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