Publications by authors named "Hyojin Kang"

54 Publications

Gene Dosage- and Age-Dependent Differential Transcriptomic Changes in the Prefrontal Cortex of -Mutant Mice.

Front Mol Neurosci 2021 11;14:683196. Epub 2021 Jun 11.

Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, South Korea.

Shank2 is an abundant postsynaptic scaffolding protein that is known to regulate excitatory synapse assembly and synaptic transmission and has been implicated in various neurodevelopmental disorders, including autism spectrum disorders (ASD). Previous studies on -mutant mice provided mechanistic insights into their autistic-like phenotypes, but it remains unclear how transcriptomic patterns are changed in brain regions of the mutant mice in age- and gene dosage-dependent manners. To this end, we performed RNA-Seq analyses of the transcripts from the prefrontal cortex (PFC) of heterozygous and homozygous -mutant mice lacking exons 6 and 7 at juvenile (week 3) and adult (week 12) stages. Juvenile heterozygous -mutant mice showed upregulation of glutamate synapse-related genes, downregulation of ribosomal and mitochondrial genes, and transcriptomic changes that are opposite to those observed in ASD (anti-ASD) such as upregulation of ASD_down (downregulated in ASD), GABA neuron-related, and oligodendrocyte-related genes. Juvenile homozygous mice showed upregulation of chromatin-related genes and transcriptomic changes that are in line with those occurring in ASD (pro-ASD) such as downregulation of ASD_down, GABA neuron-related, and oligodendrocyte-related genes. Adult heterozygous and homozygous -mutant mice both exhibited downregulation of ribosomal and mitochondrial genes and pro-ASD transcriptomic changes. Therefore, the gene dosage- and age-dependent effects of deletions in mice include differential transcriptomic changes across distinct functional contexts, including synapses, chromatin, ribosomes, mitochondria, GABA neurons, and oligodendrocytes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2021.683196DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8226033PMC
June 2021

Novel Alzheimer's disease risk variants identified based on whole-genome sequencing of APOE ε4 carriers.

Transl Psychiatry 2021 05 19;11(1):296. Epub 2021 May 19.

Clinical Genomics Center, Samsung Medical Center, Seoul, South Korea.

Alzheimer's disease (AD) is a progressive neurodegenerative disease associated with a complex genetic etiology. Besides the apolipoprotein E ε4 (APOE ε4) allele, a few dozen other genetic loci associated with AD have been identified through genome-wide association studies (GWAS) conducted mainly in individuals of European ancestry. Recently, several GWAS performed in other ethnic groups have shown the importance of replicating studies that identify previously established risk loci and searching for novel risk loci. APOE-stratified GWAS have yielded novel AD risk loci that might be masked by, or be dependent on, APOE alleles. We performed whole-genome sequencing (WGS) on DNA from blood samples of 331 AD patients and 169 elderly controls of Korean ethnicity who were APOE ε4 carriers. Based on WGS data, we designed a customized AD chip (cAD chip) for further analysis on an independent set of 543 AD patients and 894 elderly controls of the same ethnicity, regardless of their APOE ε4 allele status. Combined analysis of WGS and cAD chip data revealed that SNPs rs1890078 (P = 6.64E-07) and rs12594991 (P = 2.03E-07) in SORCS1 and CHD2 genes, respectively, are novel genetic variants among APOE ε4 carriers in the Korean population. In addition, nine possible novel variants that were rare in individuals of European ancestry but common in East Asia were identified. This study demonstrates that APOE-stratified analysis is important for understanding the genetic background of AD in different populations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41398-021-01412-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8134477PMC
May 2021

Increased ribosomal protein levels and protein synthesis in the striatal synaptosome of Shank3-overexpressing transgenic mice.

Mol Brain 2021 02 23;14(1):39. Epub 2021 Feb 23.

Department of Neuroscience, College of Medicine, Korea University, 73, Goryeodae-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.

The SH3 and multiple ankyrin repeat domains 3 (Shank3) protein is a core organizer of the macromolecular complex in excitatory postsynapses, and its defects cause numerous synaptopathies, including autism spectrum disorders. Although the function of Shank3 as a postsynaptic scaffold is adequately established, other potential mechanisms through which Shank3 broadly modulates the postsynaptic proteome remain relatively unexplored. In our previous quantitative proteomic analysis, six up-regulated ribosomal proteins were identified in the striatal synaptosome of Shank3-overexpressing transgenic (TG) mice. In the present study, we validated the increased levels of RPLP1 and RPL36A in synaptosome, but not in whole lysate, of the TG striatum. Moreover, protein synthesis and extracellular signaling-regulated kinase (ERK) activity were enhanced in the TG striatal synaptosome. To understand the potential contribution of increased protein synthesis to the proteomic change in the TG striatal synaptosome, we performed RNA-sequencing analyses on both whole synaptosomal and synaptic polysome-enriched fractions. Comparative analyses showed a positive correlation only between the polysome-associated transcriptome and up-regulated proteome in the TG striatal synaptosome. Our findings suggest a novel mechanism through which Shank3 may remodel the postsynaptic proteome by regulating synaptic protein synthesis, whose dysfunction can be implicated in SHANK3-associated synaptopathies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13041-021-00756-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7903774PMC
February 2021

The Neomycin Resistance Cassette in the Targeted Allele of Knock-Out Mice Has Potential Off-Target Effects to Produce an Unusual Shank3 Isoform.

Front Mol Neurosci 2020 11;13:614435. Epub 2021 Jan 11.

Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.

Variants of the SH3 and multiple ankyrin repeat domains 3 (), which encodes postsynaptic scaffolds, are associated with brain disorders. The targeted alleles in a few knock-out (KO) lines contain a neomycin resistance (Neo) cassette, which may perturb the normal expression of neighboring genes; however, this has not been investigated in detail. We previously reported an unexpected increase in the mRNA expression of exons 1-12 in the brains of KO mice generated by replacing exons 13-16 with the Neo cassette. In this study, we confirmed that the increased mRNA in KO brains produced an unusual ∼60 kDa Shank3 isoform (Shank3-N), which did not properly localize to the synaptic compartment. Functionally, Shank3-N overexpression altered the dendritic spine morphology in cultured neurons. Importantly, Shank3-N expression in KO mice was not a compensatory response to a reduction of full-length Shank3 because expression was still detected in the brain after normalizing the level of full-length Shank3. Moreover, in another KO line ( gKO) with a similar exonal deletion as that in KO mice but without a Neo cassette, the mRNA expression levels of exons 1-12 were lower than those of wild-type mice and Shank3-N was not detected in the brain. In addition, the expression levels of genes neighboring on chromosome 15 were altered in the striatum of KO but not gKO mice. These results suggest that the Neo cassette has potential off-target effects in KO mice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2020.614435DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7831789PMC
January 2021

SLC6A20 transporter: a novel regulator of brain glycine homeostasis and NMDAR function.

EMBO Mol Med 2021 Feb 11;13(2):e12632. Epub 2021 Jan 11.

Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea.

Glycine transporters (GlyT1 and GlyT2) that regulate levels of brain glycine, an inhibitory neurotransmitter with co-agonist activity for NMDA receptors (NMDARs), have been considered to be important targets for the treatment of brain disorders with suppressed NMDAR function such as schizophrenia. However, it remains unclear whether other amino acid transporters expressed in the brain can also regulate brain glycine levels and NMDAR function. Here, we report that SLC6A20A, an amino acid transporter known to transport proline based on in vitro data but is understudied in the brain, regulates proline and glycine levels and NMDAR function in the mouse brain. SLC6A20A transcript and protein levels were abnormally increased in mice carrying a mutant PTEN protein lacking the C terminus through enhanced β-catenin binding to the Slc6a20a gene. These mice displayed reduced extracellular levels of brain proline and glycine and decreased NMDAR currents. Elevating glycine levels back to normal ranges by antisense oligonucleotide-induced SLC6A20 knockdown, or the competitive GlyT1 antagonist sarcosine, normalized NMDAR currents and repetitive climbing behavior observed in these mice. Conversely, mice lacking SLC6A20A displayed increased extracellular glycine levels and NMDAR currents. Lastly, both mouse and human SLC6A20 proteins mediated proline and glycine transports, and SLC6A20 proteins could be detected in human neurons. These results suggest that SLC6A20 regulates proline and glycine homeostasis in the brain and that SLC6A20 inhibition has therapeutic potential for brain disorders involving NMDAR hypofunction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.15252/emmm.202012632DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7863395PMC
February 2021

Enhanced Prefrontal Neuronal Activity and Social Dominance Behavior in Postnatal Forebrain Excitatory Neuron-Specific Knock-Out Mice.

Front Mol Neurosci 2020 29;13:574947. Epub 2020 Oct 29.

Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.

The cytoplasmic fragile X mental retardation 1 (FMR1)-interacting protein 2 () gene is associated with epilepsy, intellectual disability (ID), and developmental delay, suggesting its critical role in proper neuronal development and function. CYFIP2 is involved in regulating cellular actin dynamics and also interacts with RNA-binding proteins. However, the adult brain function of CYFIP2 remains unclear because investigations thus far are limited to heterozygous ( ) mice owing to the perinatal lethality of -null mice. Therefore, we generated conditional knock-out (cKO) mice with reduced CYFIP2 expression in postnatal forebrain excitatory neurons (). We found that in the medial prefrontal cortex (mPFC) of adult cKO mice, CYFIP2 expression was decreased in both layer 2/3 (L2/3) and layer 5 (L5) neurons, unlike the L5-specific CYFIP2 reduction observed in adult mice. Nevertheless, filamentous actin (F-actin) levels were increased only in L5 of cKO mPFC possibly because of a compensatory increase in CYFIP1, the other member of CYFIP family, in L2/3 neurons. Abnormal dendritic spines on basal, but not on apical, dendrites were consistently observed in L5 neurons of cKO mPFC. Meanwhile, neuronal excitability and activity were enhanced in both L2/3 and L5 neurons of cKO mPFC, suggesting that CYFIP2 functions of regulating F-actin and excitability/activity may be mediated through independent mechanisms. Unexpectedly, adult cKO mice did not display locomotor hyperactivity or reduced anxiety observed in mice. Instead, both exhibited enhanced social dominance accessed by the tube test. Together, these results provide additional insights into the functions of CYFIP2 in the adult brain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2020.574947DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7658541PMC
October 2020

Association of long noncoding RNA MALAT1 polymorphisms with gastric cancer risk in Korean individuals.

Mol Genet Genomic Med 2020 12 2;8(12):e1541. Epub 2020 Nov 2.

Department of Internal Medicine, Chungnam National University Hospital, Chungnam National University College of Medicine, Daejeon, Republic of Korea.

Background: Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) drives tumorigenesis of various human cancers. However, the association between MALAT1 variants and gastric cancer (GC) risk is unknown. We performed a case-control study to evaluate the possible association between rs619586 and rs3200401 SNPs in MALAT and GC risk.

Methods: Samples from 458 patients with GC and 381 controls were genotyped using the TaqMan genotyping assay.

Results: In stratified analyses, we observed that rs3200401 CT in the codominant model and CT+TT in the dominant model were associated with increased GC risk in male patients (CT: odds ratio [OR] = 1.81, 95% confidence interval [CI] = 1.09-3.01, p = 0.022; CT+TT: OR = 1.74, 95% CI = 1.07-2.83, p = 0.026), and the differentiated (CT: OR =1.79, 95% CI = 1.18-2.73, p = 0.007; CT+TT: OR = 1.76, 95% CI = 1.17-2.64, p = 0.007), and intestinal (CT: OR = 1.67, 95% CI = 1.11-2.49, p = 0.013; CT+TT: OR = 1.68, 95% CI = 1.14-2.47, p = 0.009) GC subgroups.

Conclusion: MALAT1 rs3200401 increases GC susceptibility and might affect GC development. Further studies are needed to validate our results in large populations and different ethnic groups.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/mgg3.1541DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7767557PMC
December 2020

Altered presynaptic function and number of mitochondria in the medial prefrontal cortex of adult Cyfip2 heterozygous mice.

Mol Brain 2020 09 11;13(1):123. Epub 2020 Sep 11.

Department of Neuroscience, College of Medicine, Korea University, 73, Goryeodae-ro, Seongbuk-gu, Seoul, 02841, South Korea.

Variants of the cytoplasmic FMR1-interacting protein (CYFIP) gene family, CYFIP1 and CYFIP2, are associated with numerous neurodevelopmental and neuropsychiatric disorders. According to several studies, CYFIP1 regulates the development and function of both pre- and post-synapses in neurons. Furthermore, various studies have evaluated CYFIP2 functions in the postsynaptic compartment, such as regulating dendritic spine morphology; however, no study has evaluated whether and how CYFIP2 affects presynaptic functions. To address this issue, in this study, we have focused on the presynapses of layer 5 neurons of the medial prefrontal cortex (mPFC) in adult Cyfip2 heterozygous (Cyfip2) mice. Electrophysiological analyses revealed an enhancement in the presynaptic short-term plasticity induced by high-frequency stimuli in Cyfip2 neurons compared with wild-type neurons. Since presynaptic mitochondria play an important role in buffering presynaptic Ca, which is directly associated with the short-term plasticity, we analyzed presynaptic mitochondria using electron microscopic images of the mPFC. Compared with wild-type mice, the number, but not the volume or cristae density, of mitochondria in both presynaptic boutons and axonal processes in the mPFC layer 5 of Cyfip2 mice was reduced. Consistent with an identification of mitochondrial proteins in a previously established CYFIP2 interactome, CYFIP2 was detected in a biochemically enriched mitochondrial fraction of the mouse mPFC. Collectively, these results suggest roles for CYFIP2 in regulating presynaptic functions, which may involve presynaptic mitochondrial changes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13041-020-00668-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7488858PMC
September 2020

Haploinsufficiency of Cyfip2 Causes Lithium-Responsive Prefrontal Dysfunction.

Ann Neurol 2020 09 27;88(3):526-543. Epub 2020 Jul 27.

Department of Neuroscience, College of Medicine, Korea University.

Objective: Genetic variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) encoding an actin-regulatory protein are associated with brain disorders, including intellectual disability and epilepsy. However, specific in vivo neuronal defects and potential treatments for CYFIP2-associated brain disorders remain largely unknown. Here, we characterized Cyfip2 heterozygous (Cyfip2 ) mice to understand their neurobehavioral phenotypes and the underlying pathological mechanisms. Furthermore, we examined a potential treatment for such phenotypes of the Cyfip2 mice and specified a neuronal function mediating its efficacy.

Methods: We performed behavioral analyses of Cyfip2 mice. We combined molecular, ultrastructural, and in vitro and in vivo electrophysiological analyses of Cyfip2 prefrontal neurons. We also selectively reduced CYFIP2 in the prefrontal cortex (PFC) of mice with virus injections.

Results: Adult Cyfip2 mice exhibited lithium-responsive abnormal behaviors. We found increased filamentous actin, enlarged dendritic spines, and enhanced excitatory synaptic transmission and excitability in the adult Cyfip2 PFC that was restricted to layer 5 (L5) neurons. Consistently, adult Cyfip2 mice showed increased seizure susceptibility and auditory steady-state responses from the cortical electroencephalographic recordings. Among the identified prefrontal defects, lithium selectively normalized the hyperexcitability of Cyfip2 L5 neurons. RNA sequencing revealed reduced expression of potassium channel genes in the adult Cyfip2 PFC. Virus-mediated reduction of CYFIP2 in the PFC was sufficient to induce L5 hyperexcitability and lithium-responsive abnormal behavior.

Interpretation: These results suggest that L5-specific prefrontal dysfunction, especially hyperexcitability, underlies both the pathophysiology and the lithium-mediated amelioration of neurobehavioral phenotypes in adult Cyfip2 mice, which can be implicated in CYFIP2-associated brain disorders. ANN NEUROL 2020;88:526-543.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ana.25827DOI Listing
September 2020

Epilepsy- and intellectual disability-associated CYFIP2 interacts with both actin regulators and RNA-binding proteins in the neonatal mouse forebrain.

Biochem Biophys Res Commun 2020 08 5;529(1):1-6. Epub 2020 Jun 5.

Department of Neuroscience, College of Medicine, Korea University, Seoul, 02841, South Korea; Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, 02841, South Korea. Electronic address:

Variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) gene are associated with early-onset epileptic encephalopathy, intellectual disability, and developmental delay. However, the current understanding of the molecular functions of CYFIP2 is limited to those related to actin dynamics, and thus, the detailed mechanisms of CYFIP2-associated brain disorders remain largely unknown. Here, we isolated the neonatal forebrain CYFIP2 complex using newly generated Cyfip2-3×Flag knock-in mice, and performed mass spectrometry-based analyses to identify proteins in the complex. The CYFIP2 interactome, consisting of 140 proteins, contained not only the expected actin regulators but also 25 RNA-binding proteins (RBPs) including Argonaute proteins. Functionally, overexpression of brain disorder-associated CYFIP2 R87 variants, but not wild-type, inhibited stress granule formation in HeLa cells. Mechanistically, the CYFIP2 R87 variants formed intracellular clusters with Argonaute proteins under both basal and stress conditions, and thereby possibly preventing their assembly into stress granules. Beyond identifying CYFIP2 interactors in vivo, these results may provide novel insights for better understanding the molecular mechanisms of CYFIP2-associated brain disorders.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2020.05.221DOI Listing
August 2020

Association Between lncRNA HULC rs7763881 Polymorphism and Gastric Cancer Risk.

Pharmgenomics Pers Med 2020 9;13:121-126. Epub 2020 Apr 9.

Department of Internal Medicine, Chungnam National University Hospital, Chungnam National University College of Medicine, Daejeon, Republic of Korea.

Purpose: Gastric cancer (GC) is one of the most common cancers in the world. Recently, several studies have suggested that single-nucleotide polymorphisms (SNPs) of long noncoding RNA (lncRNA) are associated with GC risk. However, the association of the lncRNA highly upregulated in liver cancer () SNP with GC risk is not yet known. The aims of this study were to evaluate the association between rs7763881 SNP and the risk of GC and GC subgroups via a case-control study.

Patients And Methods: rs7763881 was genotyped using TaqMan genotyping assay with 459 GC patients and 379 controls.

Results: A significant association between rs7763881 SNP and GC risk was not found. However, after adjustment for age and gender, the rs7763881 recessive model (CC) showed a significant association with an increased GC risk in the undifferentiated (odds ratio (OR) = 1.85, 95% confidence interval (CI) = 1.17-2.94, = 0.009), diffuse-type GC (OR = 1.72, 95% CI = 1.05-2.82, = 0.033), LNM-positive (OR = 2.02, 95% CI = 1.24-3.27, = 0.004), T3/T4 (OR = 1.75, 95% CI = 1.05-2.91, = 0.032), and tumor stage III (OR = 2.01, 95% CI = 1.17-3.45, = 0.011) subgroups when compared to the rs7763881 combined genotypes (AA+AC). Furthermore, after adjusting for age and gender, the rs7763881 additive model (CC) indicated a significantly higher GC risk than rs7763881 AA genotype in the undifferentiated (OR = 1.96, 95% CI = 1.15-3.32, = 0.013), diffuse-type GC (OR = 2.08, 95% CI = 1.23-3.52, = 0.004), and LNM-positive (OR = 2.00, 95% CI = 1.14-3.49, = 0.016) subgroups.

Conclusion: Our findings suggest that the rs7763881 SNP is associated with increased susceptibility to GC. However, further studies are required to validate our results in large populations as well as different ethnic groups.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/PGPM.S247082DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7154033PMC
April 2020

Effect of Antioxidant Addition on Milk Beverage Supplemented with Coffee and Shelf-life Prediction.

Food Sci Anim Resour 2019 Dec 31;39(6):903-917. Epub 2019 Dec 31.

Department of Animal Industry Convergence, College of Animal Life Sciences, Kangwon National University, Chuncheon 24341, Korea.

This study aimed to extend the shelf-life of coffee-containing milk beverage by adding (cacao nibs) extract. To prepare the beverage sample containing cacao nibs extract, 0.8% cacao nibs hydrothermal extract was aseptically injected. Qualitative changes in the beverage samples, including antioxidant effect, peroxide value (POV), caffeine content, and sensory parameters were monitored regularly during storage at 10°C, 20°C, and 30°C for 4 wk. The inclusion of cacao nibs extract produced higher antioxidant activity compared to the control. As the storage temperature increased, the POV of all samples increased. Samples with cacao nibs extract generally displayed lower POV than the control. The caffeine content of all samples tended to decrease during storage, with the decrease accentuated by higher storage temperatures. In the shelf-life prediction using the Arrhenius model, the kinetic regressions of the cacao nibs extract-added sample and control were =1.2212-2.1141 (r=0.9713) and =1.8075-2.0189 (r=0.9883), respectively. Finally, the predicted shelf-life of cacao nibs-added group and control to reach the quality limit (20 meq/kg POV) were approximately 18.11 and 12.18 wk, respectively. The results collectively indicate that the addition of cacao nibs extract extends the shelf-life of the coffee-containing milk beverage and heightened the antioxidant effect.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5851/kosfa.2019.e76DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6949520PMC
December 2019

Microencapsulation of Caramel Flavor and Properties of Ready-to-drink Milk Beverages Supplemented with Coffee Containing These Microcapsules.

Food Sci Anim Resour 2019 Oct 31;39(5):780-791. Epub 2019 Oct 31.

Department of Animal Industry Convergence, College of Animal Life Sciences, Kangwon National University, Chuncheon 24341, Korea.

This study aimed to extend the retention of flavor in coffee-containing milk beverage by microencapsulation. The core material was caramel flavor, and the primary and secondary coating materials were medium-chain triglyceride and maltodextrin, respectively. Polyglycerol polyricinoleate was used as the primary emulsifier, and the secondary emulsifier was polyoxyethylene sorbitan monolaurate. Response surface methodology was employed to determine optimum microencapsulation conditions, and headspace solid-phase microextraction was used to detect the caramel flavor during storage. The microencapsulation yield of the caramel flavor increased as the ratio of primary to secondary coating material increased. The optimum ratio of core to primary coating material for the water-in-oil (W/O) phase was 1:9, and that of the W/O phase to the secondary coating material was also 1:9. Microencapsulation yield was observed to be approximately 93.43%. In case of release behavior, the release rate of the capsules in the simulated gastric environment was feeble; however, the release rate in the simulated intestinal environment rapidly increased within 30 min, and nearly 70% of the core material was released within 120 min. The caramel flavor-supplemented beverage sample exhibited an exponential degradation in its flavor components. However, microcapsules containing flavor samples showed sustained flavor release compared to caramel flavor-filled samples under higher storage temperatures. In conclusion, the addition of coffee flavor microcapsules to coffee-containing milk beverages effectively extended the retention of the coffee flavor during the storage period.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5851/kosfa.2019.e68DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6837899PMC
October 2019

A TBR1-K228E Mutation Induces Upregulation, Altered Cortical Distribution of Interneurons, Increased Inhibitory Synaptic Transmission, and Autistic-Like Behavioral Deficits in Mice.

Front Mol Neurosci 2019 9;12:241. Epub 2019 Oct 9.

College of Pharmacy, Yeongnam University, Gyeongsan, South Korea.

Mutations in , a high-confidence ASD (autism spectrum disorder)-risk gene encoding the transcriptional regulator TBR1, have been shown to induce diverse ASD-related molecular, synaptic, neuronal, and behavioral dysfunctions in mice. However, whether mutations derived from autistic individuals cause similar dysfunctions in mice remains unclear. Here we generated and characterized mice carrying the TBR1-K228E mutation identified in human ASD and identified various ASD-related phenotypes. In heterozygous mice carrying this mutation ( mice), levels of the TBR1-K228E protein, which is unable to bind target DNA, were strongly increased. RNA-Seq analysis of the embryonic brain indicated significant changes in the expression of genes associated with neurons, astrocytes, ribosomes, neuronal synapses, and ASD risk. The neocortex also displayed an abnormal distribution of parvalbumin-positive interneurons, with a lower density in superficial layers but a higher density in deep layers. These changes were associated with an increase in inhibitory synaptic transmission in layer 6 pyramidal neurons that was resistant to compensation by network activity. Behaviorally, mice showed decreased social interaction, increased self-grooming, and modestly increased anxiety-like behaviors. These results suggest that the human heterozygous TBR1-K228E mutation induces ASD-related transcriptomic, protein, neuronal, synaptic, and behavioral dysfunctions in mice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2019.00241DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6797848PMC
October 2019

Unexpected Compensatory Increase in Transcripts in Knock-Out Mice Having Partial Deletions of Exons.

Front Mol Neurosci 2019 19;12:228. Epub 2019 Sep 19.

Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.

Genetic variants of the SH3 and multiple ankyrin repeat domains 3 () gene, which encodes excitatory postsynaptic core scaffolds cause numerous brain disorders. Several lines of knock-out (KO) mice with deletions of different exons have previously been generated and characterized. The different KO mouse lines have both common and line-specific phenotypes. Shank3 isoform diversity is considered a mechanism underlying phenotypic heterogeneity, and compensatory changes through regulation of expression may contribute to this heterogeneity. However, whether such compensatory changes occur in KO mouse lines has not been investigated in detail. Using previously reported RNA-sequencing analyses, we identified an unexpected increase in transcripts in two different mutant mouse lines ( and ) having partial deletions of exons. We validated an increase in transcripts in the hippocampus, cortex, and striatum, but not in the cerebellum, of heterozygous (HET) and KO mice, using qRT-PCR analyses. In particular, expression of the N-terminal exons 1-12, but not the more C-terminal exons 19-22, was observed to increase in mice with deletion of exons 13-16. This suggests a selective compensatory activation of upstream promoters. Furthermore, using domain-specific Shank3 antibodies, we confirmed that the increased transcripts in KO mice produced a small Shank3 isoform that was not detected in wild-type mice. Taken together, our results illustrate another layer of complexity in the regulation of expression in the brain, which may also contribute to the phenotypic heterogeneity of different KO mouse lines.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2019.00228DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6761322PMC
September 2019

Transcriptome analyses suggest minimal effects of Shank3 dosage on directional gene expression changes in the mouse striatum.

Anim Cells Syst (Seoul) 2019 12;23(4):270-274. Epub 2019 Apr 12.

Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.

Both deletions and duplications of the SH3 and multiple ankyrin repeat domains 3 () gene, encoding excitatory postsynaptic scaffolds, are causally associated with various brain disorders, suggesting that proper Shank3 dosage is critical for normal brain development and function. In addition to its well-established synaptic functions, recent studies have suggested that Shank3 can also affect gene expression in the nucleus. However, it has not been investigated whether there are a group of genes whose directional expression is regulated in a Shank3 dosage-dependent manner (i.e. showing opposite changes in expression following Shank3 reduction and overexpression). This is an important issue to be examined for better understanding why neuronal development and function are sensitive to Shank3 dosage, and how much transcriptional changes contribute to neuronal phenotypes affected by Shank3 dosage. To examine this, we performed transcriptome analyses on the striatum of heterozygous and knock-out mice, which identified three and 17 differentially expressed genes, respectively. We then compared the results to those of our previous striatal transcriptome analysis of overexpressing mice and identified 31 candidate genes showing directional expression changes in a Shank3 dosage-dependent manner. However, overall, their Shank3 dosage-dependent fold changes were very subtle (average of absolute log2(fold change) was 0.139). Meanwhile, the gene set enrichment analyses of the striatal transcriptome suggested that Shank3 dosage may affect anchoring junction-related functions. Taken together, these results suggest that Shank3 dosage minimally affects directional gene expression changes in the mouse striatum.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/19768354.2019.1595142DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6711111PMC
April 2019

Correlations between Genetic Polymorphisms in Long Non-Coding RNA and Gastric Cancer Risk in a Korean Population.

Int J Mol Sci 2019 Jul 8;20(13). Epub 2019 Jul 8.

Department of Internal Medicine, Chungnam National University Hospital, Chungnam National University College of Medicine, Daejeon 35015, Korea.

We evaluated the association between prostate cancer non-coding RNA 1 () polymorphisms and the risk of developing gastric cancer (GC) and GC subgroups in Korea. A case-control study was conducted with 437 GC patients and 357 healthy controls using a TaqMan genotyping assay. A chi-squared test, binary logistic regression, and genetic models were used to explore the association between five polymorphisms and GC risk. After adjusting for gender and age, overall analyses using the recessive model indicated that the rs13252298 GG genotype was significantly associated with increased risk of intestinal-type gastric cancer (IGC). In the stratification analyses, the recessive model indicated that the rs1016343 TT genotype was significantly associated with decreased GC risk in individuals aged <60 years showing lymph node metastasis (LNM)-negative results. The rs13252298 GG genotype in the recessive model showed increased GC risk in subjects aged ≥60 years showing LNM-positive results and those aged ≥60 years in tumor stage III. In the dominant model, the rs16901946 combined genotype (AG/GG) was significantly associated with increased GC risk in subjects aged <60 years with tumor stage III. In the recessive model, the rs16901946 GG genotype was associated with decreased risk of GC and IGC in males aged ≥60 years. Thus, genetic variations in may contribute to susceptibility to GC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms20133355DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6650882PMC
July 2019

Shank3 regulates striatal synaptic abundance of Cyld, a deubiquitinase specific for Lys63-linked polyubiquitin chains.

J Neurochem 2019 09 11;150(6):776-786. Epub 2019 Jul 11.

Departments of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.

The SH3 and multiple ankyrin repeat domains 3 (Shank3) proteins are core organizers of the postsynaptic density in neuronal excitatory synapses, and their defects cause various neurodevelopmental and neuropsychiatric disorders. Mechanistically, Shank3 directly and indirectly interacts with hundreds of synaptic proteins with diverse functions and potentially exerts its regulatory roles in synaptic development and function via these interactors. However, Shank3-dependent regulation of synaptic abundance has been validated in vivo for only a few Shank3 interactors. Here, using a quantitative proteomic analysis, we identified 136 proteins with altered synaptic abundance in the striatum of Shank3-overexpressing transgenic (TG) mice. By comparing these proteins with those found in a previous analysis of the postsynaptic density of Shank3 knock-out (KO) striatum, we identified and confirmed that cylindromatosis-associated deubiquitinase (Cyld), a deubiquitinase specific for Lys63-linked polyubiquitin chains, was up- and down-regulated in Shank3 TG and KO striatal synapses, respectively. Consistently, we found that the synaptic levels of Lys63-linked polyubiquitin chains were down- and up-regulated in the Shank3 TG and KO striata, respectively. Furthermore, by isolating and analyzing the synaptic Cyld complex, we generated a Cyld interactome consisting of 103 proteins, which may include Cyld substrates. Bioinformatic analyses suggested associations of the Cyld interactome with a few brain disorders and synaptic functions. Taken together, these results suggest that Shank3 regulates the synaptic abundance of Cyld in the mouse striatum and, thereby, potentially modulates the Lys63-linked polyubiquitination of striatal synaptic proteins.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jnc.14796DOI Listing
September 2019

Comparing Properties of Variable Pore-Sized 3D-Printed PLA Membrane with Conventional PLA Membrane for Guided Bone/Tissue Regeneration.

Materials (Basel) 2019 May 27;12(10). Epub 2019 May 27.

Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seoul 03722, Korea.

The aim of this study was to fabricate bioresorbable polylactide (PLA) membranes by 3D printing and compare their properties to those of the membranes fabricated by the conventional method and compare the effect of different pore sizes on the properties of the 3D-printed membranes. PLA membranes with three different pore sizes (large pore-479 μm, small pore-273 μm, and no pore) were 3D printed, and membranes fabricated using the conventional solvent casting method were used as the control group. Scanning electron microscopy (SEM) and micro-computed tomography (µ-CT) were taken to observe the morphology and obtain the porosity of the four groups. A tensile test was performed to compare the tensile strength, elastic modulus, and elongation at break of the membranes. Preosteoblast cells were cultured on the membranes for 1, 3 and 7 days, followed by a WST assay and SEM, to examine the cell proliferation on different groups. As a result, the 3D-printed membranes showed superior mechanical properties to those of the solvent cast membranes, and the 3D-printed membranes exhibited different advantageous mechanical properties depending on the different pore sizes. The various fabrication methods and pore sizes did not have significantly different effects on cell growth. It is proven that 3D printing is a promising method for the fabrication of customized barrier membranes used in GBR/GTR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ma12101718DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6566256PMC
May 2019

Smaller Body Size, Early Postnatal Lethality, and Cortical Extracellular Matrix-Related Gene Expression Changes of -Null Embryonic Mice.

Front Mol Neurosci 2018 4;11:482. Epub 2019 Jan 4.

Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.

Cytoplasmic FMR1-interacting protein 2 (CYFIP2) is a key component of the WAVE regulatory complex (WRC) which regulates actin polymerization and branching in diverse cellular compartments. Recent whole exome sequencing studies identified hotspot variants in from patients with early-onset epileptic encephalopathy and microcephaly, suggesting that CYFIP2 may have some functions in embryonic brain development. Although perinatal lethality of -null ( ) mice was reported, the exact developmental time point and cause of lethality, and whether embryonic mice have brain abnormalities remain unknown. We found that endogenous is mainly expressed in the brain, spinal cord, and thymus of mice at late embryonic stages. embryos did not show lethality at embryonic day 18.5 (E18.5), but their body size was smaller than that of wild-type (WT) or littermates. Meanwhile, at postnatal day 0, all identified mice were found dead, suggesting early postnatal lethality of the mice. Nevertheless, the brain size and cortical cytoarchitecture were comparable among WT, , and mice at E18.5. Using RNA-sequencing analyses, we identified 98 and 72 differentially expressed genes (DEGs) from the E18.5 cortex of and mice, respectively. Further bioinformatic analyses suggested that extracellular matrix (ECM)-related gene expression changes in embryonic cortex. Together, our results suggest that CYFIP2 is critical for embryonic body growth and for early postnatal survival, and that loss of its expression leads to ECM-related gene expression changes in the embryonic cortex without severe gross morphological defects.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2018.00482DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6338024PMC
January 2019

Transcriptome analysis of Shank3-overexpressing mice reveals unique molecular changes in the hypothalamus.

Mol Brain 2018 11 27;11(1):71. Epub 2018 Nov 27.

Department of Neuroscience, College of Medicine, Korea University, 73, Inchon-ro, Seongbuk-gu, Seoul, 02841, South Korea.

Various mutations in the SH3 and multiple ankyrin repeat domains 3 (SHANK3) gene are associated with neurodevelopmental and neuropsychiatric disorders. Thus far, synaptic abnormalities in multiple brain regions, including the hippocampus, prefrontal cortex, striatum, and ventral tegmental area, have been investigated in several lines of Shank3 mutant mice. However, although some reports have shown loss and gain of body weight in Shank3 knock-out and overexpressing transgenic (TG) mice, respectively, the potential functions of Shank3 in the hypothalamus, a brain region critically involved in energy intake and expenditure, are unknown. Hence, we first characterized endogenous Shank3 mRNA and protein expression in the hypothalamus of adult wild-type mice. Thereafter, we performed transcriptome analysis (RNA-sequencing) in the hypothalamus of adult Shank3 TG mice which mildly overexpress Shank3 proteins. By comparing the 174 differentially expressed genes in the hypothalamus with those previously reported in the striatum and medial prefrontal cortex (mPFC) of Shank3 TG mice, we found that 159 were hypothalamus-specific while only 15 were also observed in either the striatum or mPFC. Furthermore, gene set enrichment analysis of the RNA-sequencing analysis revealed that ribosome-related genes were enriched especially in the up-regulated genes of Shank3 TG hypothalamus, which is in contrast to the results of the Shank3 TG striatum and mPFC analyses, where ribosome-related genes were enriched in the down-regulated genes. Beyond revealing endogenous Shank3 mRNA and protein expression in the hypothalamus, our results suggest unique molecular changes in the hypothalamus of Shank3 TG mice compared with those in the striatum and mPFC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13041-018-0413-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6257967PMC
November 2018

Early Correction of N-Methyl-D-Aspartate Receptor Function Improves Autistic-like Social Behaviors in Adult Shank2 Mice.

Biol Psychiatry 2019 04 9;85(7):534-543. Epub 2018 Oct 9.

Department of Biological Sciences, South Korea; Center for Synaptic Brain Dysfunctions, Institute for Basic Science, South Korea. Electronic address:

Background: Autism spectrum disorder involves neurodevelopmental dysregulations that lead to visible symptoms at early stages of life. Many autism spectrum disorder-related mechanisms suggested by animal studies are supported by demonstrated improvement in autistic-like phenotypes in adult animals following experimental reversal of dysregulated mechanisms. However, whether such mechanisms also act at earlier stages to cause autistic-like phenotypes is unclear.

Methods: We used Shank2 mice carrying a mutation identified in human autism spectrum disorder (exons 6 and 7 deletion) and combined electrophysiological and behavioral analyses to see whether early pathophysiology at pup stages is different from late pathophysiology at juvenile and adult stages and whether correcting early pathophysiology can normalize late pathophysiology and abnormal behaviors in juvenile and adult mice.

Results: Early correction of a dysregulated mechanism in young mice prevents manifestation of autistic-like social behaviors in adult mice. Shank2 mice, known to display N-methyl-D-aspartate receptor (NMDAR) hypofunction and autistic-like behaviors at postweaning stages after postnatal day 21 (P21), show the opposite synaptic phenotype-NMDAR hyperfunction-at an earlier preweaning stage (∼P14). Moreover, this NMDAR hyperfunction at P14 rapidly shifts to NMDAR hypofunction after weaning (∼P24). Chronic suppression of the early NMDAR hyperfunction by the NMDAR antagonist memantine (P7-P21) prevents NMDAR hypofunction and autistic-like social behaviors from manifesting at later stages (∼P28 and P56).

Conclusions: Early NMDAR hyperfunction leads to late NMDAR hypofunction and autistic-like social behaviors in Shank2 mice, and early correction of NMDAR dysfunction has the long-lasting effect of preventing autistic-like social behaviors from developing at later stages.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biopsych.2018.09.025DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6420362PMC
April 2019

A Druggable Genome Screen Identifies Modifiers of α-Synuclein Levels via a Tiered Cross-Species Validation Approach.

J Neurosci 2018 10 24;38(43):9286-9301. Epub 2018 Sep 24.

Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, 77030, Texas,

Accumulation of α-Synuclein (α-Syn) causes Parkinson's disease (PD) as well as other synucleopathies. α-Syn is the major component of Lewy bodies and Lewy neurites, the proteinaceous aggregates that are a hallmark of sporadic PD. In familial forms of PD, mutations or copy number variations in (the α-Syn gene) result in a net increase of its protein levels. Furthermore, common risk variants tied to PD are associated with small increases of α-Syn levels. These findings are further bolstered by animal studies which show that overexpression of α-Syn is sufficient to cause PD-like features. Thus, increased α-Syn levels are intrinsically tied to PD pathogenesis and underscore the importance of identifying the factors that regulate its levels. In this study, we establish a pooled RNAi screening approach and validation pipeline to probe the druggable genome for modifiers of α-Syn levels and identify 60 promising targets. Using a cross-species, tiered validation approach, we validate six strong candidates that modulate α-Syn levels and toxicity in cell lines, , human neurons, and mouse brain of both sexes. More broadly, this genetic strategy and validation pipeline can be applied for the identification of therapeutic targets for disorders driven by dosage-sensitive proteins. We present a research strategy for the systematic identification and validation of genes modulating the levels of α-Synuclein, a protein involved in Parkinson's disease. A cell-based screen of the druggable genome (>7,500 genes that are potential therapeutic targets) yielded many modulators of α-Synuclein that were subsequently confirmed and validated in , human neurons, and mouse brain. This approach has broad applicability to the multitude of neurological diseases that are caused by mutations in genes whose dosage is critical for brain function.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1523/JNEUROSCI.0254-18.2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6199406PMC
October 2018

Integrative Brain Transcriptome Analysis Reveals Region-Specific and Broad Molecular Changes in -Overexpressing Mice.

Front Mol Neurosci 2018 31;11:250. Epub 2018 Aug 31.

Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.

Variants of the SH3 and multiple ankyrin repeat domain 3 () gene, encoding excitatory postsynaptic core scaffolding proteins, are causally associated with numerous neurodevelopmental and neuropsychiatric disorders, including autism spectrum disorder (ASD), bipolar disorder, intellectual disability, and schizophrenia (SCZ). Although detailed synaptic changes of various mutant mice have been well characterized, broader downstream molecular changes, including direct and indirect changes, remain largely unknown. To address this issue, we performed a transcriptome analysis of the medial prefrontal cortex (mPFC) of adult -overexpressing transgenic (TG) mice, using an RNA-sequencing approach. We also re-analyzed previously reported RNA-sequencing results of the striatum of adult TG mice and of the prefrontal cortex of juvenile mice with a 50-70% reduction of Shank3 proteins. We found that several myelin-related genes were significantly downregulated specifically in the mPFC, but not in the striatum or hippocampus, of adult TG mice by comparing the differentially expressed genes (DEGs) of the analyses side by side. Moreover, we also found nine common DEGs between the mPFC and striatum of TG mice, among which we further characterized ASD- and SCZ-associated G protein-coupled receptor 85 (), encoding an orphan interacting with PSD-95. Unlike the mPFC-specific decrease of myelin-related genes, we found that the mRNA levels of increased in multiple brain regions of adult TG mice, whereas the mRNA levels of its family members, and , decreased in the cortex and striatum. Intriguingly, in cultured neurons, the mRNA levels of , , and were modulated by the neuronal activity. Furthermore, exogenously expressed GPR85 was co-localized with PSD-95 and Shank3 in cultured neurons and negatively regulated the number of excitatory synapses, suggesting its potential role in homeostatic regulation of excitatory synapses in TG neurons. Finally, we performed a gene set enrichment analysis of the RNA-sequencing results, which suggested that Shank3 could affect the directional expression pattern of numerous ribosome-related genes in a dosage-dependent manner. To sum up, these results reveal previously unidentified brain region-specific and broad molecular changes in -overexpressing mice, further elucidating the complexity of the molecular pathophysiology of -associated brain disorders.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2018.00250DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6127286PMC
August 2018

Sexually dimorphic behavior, neuronal activity, and gene expression in Chd8-mutant mice.

Nat Neurosci 2018 09 13;21(9):1218-1228. Epub 2018 Aug 13.

Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea.

Autism spectrum disorders (ASDs) are four times more common in males than in females, but the underlying mechanisms are poorly understood. We characterized sexually dimorphic changes in mice carrying a heterozygous mutation in Chd8 (Chd8) that was first identified in human CHD8 (Asn2373LysfsX2), a strong ASD-risk gene that encodes a chromatin remodeler. Notably, although male mutant mice displayed a range of abnormal behaviors during pup, juvenile, and adult stages, including enhanced mother-seeking ultrasonic vocalization, enhanced attachment to reunited mothers, and isolation-induced self-grooming, their female counterparts do not. This behavioral divergence was associated with sexually dimorphic changes in neuronal activity, synaptic transmission, and transcriptomic profiles. Specifically, female mice displayed suppressed baseline neuronal excitation, enhanced inhibitory synaptic transmission and neuronal firing, and increased expression of genes associated with extracellular vesicles and the extracellular matrix. Our results suggest that a human CHD8 mutation leads to sexually dimorphic changes ranging from transcription to behavior in mice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41593-018-0208-zDOI Listing
September 2018

Characterization of the zinc-induced Shank3 interactome of mouse synaptosome.

Biochem Biophys Res Commun 2017 12 28;494(3-4):581-586. Epub 2017 Oct 28.

Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea; Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, South Korea. Electronic address:

Variants of the SHANK3 gene, which encodes a core scaffold protein of the postsynaptic density of excitatory synapses, have been causally associated with numerous brain disorders. Shank3 proteins directly bind zinc ions through their C-terminal sterile α motif domain, which enhances the multimerization and synaptic localization of Shank3, to regulate excitatory synaptic strength. However, no studies have explored whether zinc affects the protein interactions of Shank3, which might contribute to the synaptic changes observed after zinc application. To examine this, we first purified Shank3 protein complexes from mouse brain synaptosomal lysates that were incubated with different concentrations of ZnCl, and analyzed them with mass spectrometry. We used strict criteria to identify 71 proteins that specifically interacted with Shank3 when extra ZnCl was added to the lysate. To characterize the zinc-induced Shank3 interactome, we performed various bioinformatic analyses that revealed significant associations of the interactome with subcellular compartments, including mitochondria, and brain disorders, such as bipolar disorder and schizophrenia. Together, our results showing that zinc affected the Shank3 protein interactions of in vitro mouse synaptosomes provided an additional link between zinc and core synaptic proteins that have been implicated in multiple brain disorders.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2017.10.143DOI Listing
December 2017

Striatal Transcriptome and Interactome Analysis of -overexpressing Mice Reveals the Connectivity between Shank3 and mTORC1 Signaling.

Front Mol Neurosci 2017 28;10:201. Epub 2017 Jun 28.

Department of Neuroscience, College of Medicine, Korea UniversitySeoul, South Korea.

Mania causes symptoms of hyperactivity, impulsivity, elevated mood, reduced anxiety and decreased need for sleep, which suggests that the dysfunction of the striatum, a critical component of the brain motor and reward system, can be causally associated with mania. However, detailed molecular pathophysiology underlying the striatal dysfunction in mania remains largely unknown. In this study, we aimed to identify the molecular pathways showing alterations in the striatum of SH3 and multiple ankyrin repeat domains 3 (Shank3)-overexpressing transgenic (TG) mice that display manic-like behaviors. The results of transcriptome analysis suggested that mammalian target of rapamycin complex 1 (mTORC1) signaling may be the primary molecular signature altered in the TG striatum. Indeed, we found that striatal mTORC1 activity, as measured by mTOR S2448 phosphorylation, was significantly decreased in the TG mice compared to wild-type (WT) mice. To elucidate the potential underlying mechanism, we re-analyzed previously reported protein interactomes, and detected a high connectivity between Shank3 and several upstream regulators of mTORC1, such as tuberous sclerosis 1 (TSC1), TSC2 and Ras homolog enriched in striatum (Rhes), via 94 common interactors that we denominated "Shank3-mTORC1 interactome". We noticed that, among the 94 common interactors, 11 proteins were related to actin filaments, the level of which was increased in the dorsal striatum of TG mice. Furthermore, we could co-immunoprecipitate Shank3, Rhes and Wiskott-Aldrich syndrome protein family verprolin-homologous protein 1 (WAVE1) proteins from the striatal lysate of TG mice. By comparing with the gene sets of psychiatric disorders, we also observed that the 94 proteins of Shank3-mTORC1 interactome were significantly associated with bipolar disorder (BD). Altogether, our results suggest a protein interaction-mediated connectivity between Shank3 and certain upstream regulators of mTORC1 that might contribute to the abnormal striatal mTORC1 activity and to the manic-like behaviors of TG mice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2017.00201DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5487420PMC
June 2017

Integrative Analysis of Brain Region-specific Shank3 Interactomes for Understanding the Heterogeneity of Neuronal Pathophysiology Related to Mutations.

Front Mol Neurosci 2017 19;10:110. Epub 2017 Apr 19.

Department of Neuroscience, College of Medicine, Korea UniversitySeoul, South Korea.

Recent molecular genetic studies have identified 100s of risk genes for various neurodevelopmental and neuropsychiatric disorders. As the number of risk genes increases, it is becoming clear that different mutations of a single gene could cause different types of disorders. One of the best examples of such a gene is , which encodes a core scaffold protein of the neuronal excitatory post-synapse. Deletions, duplications, and point mutations of are associated with autism spectrum disorders, intellectual disability, schizophrenia, bipolar disorder, and attention deficit hyperactivity disorder. Nevertheless, how the different mutations of can lead to such phenotypic diversity remains largely unknown. In this study, we investigated whether Shank3 could form protein complexes in a brain region-specific manner, which might contribute to the heterogeneity of neuronal pathophysiology caused by mutations. To test this, we generated a medial prefrontal cortex (mPFC) Shank3 interactome consisting of 211 proteins, and compared this protein list with a Shank3 interactome previously generated from mixed hippocampal and striatal (HP+STR) tissues. Unexpectedly, we found that only 47 proteins (about 20%) were common between the two interactomes, while 164 and 208 proteins were specifically identified in the mPFC and HP+STR interactomes, respectively. Each of the mPFC- and HP+STR-specific Shank3 interactomes represents a highly interconnected network. Upon comparing the brain region-enriched proteomes, we found that the large difference between the mPFC and HP+STR Shank3 interactomes could not be explained by differential protein expression profiles among the brain regions. Importantly, bioinformatic pathway analysis revealed that the representative biological functions of the mPFC- and HP+STR-specific Shank3 interactomes were different, suggesting that these interactors could mediate the brain region-specific functions of Shank3. Meanwhile, the same analysis on the common Shank3 interactors, including Homer and GKAP/SAPAP proteins, suggested that they could mainly function as scaffolding proteins at the post-synaptic density. Lastly, we found that the mPFC- and HP+STR-specific Shank3 interactomes contained a significant number of proteins associated with neurodevelopmental and neuropsychiatric disorders. These results suggest that Shank3 can form protein complexes in a brain region-specific manner, which might contribute to the pathophysiological and phenotypic diversity of disorders related to mutations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnmol.2017.00110DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5395616PMC
April 2017

Bipolar Disorder Associated microRNA, miR-1908-5p, Regulates the Expression of Genes Functioning in Neuronal Glutamatergic Synapses.

Exp Neurobiol 2016 Dec 28;25(6):296-306. Epub 2016 Oct 28.

Department of Neuroscience and Division of Brain Korea 21 Biomedical Science, Korea University College of Medicine, Seoul 02841, Korea.

Bipolar disorder (BD), characterized by recurrent mood swings between depression and mania, is a highly heritable and devastating mental illness with poorly defined pathophysiology. Recent genome-wide molecular genetic studies have identified several protein-coding genes and microRNAs (miRNAs) significantly associated with BD. Notably, some of the proteins expressed from BD-associated genes function in neuronal synapses, suggesting that abnormalities in synaptic function could be one of the key pathogenic mechanisms of BD. In contrast, however, the role of BD-associated miRNAs in disease pathogenesis remains largely unknown, mainly because of a lack of understanding about their target mRNAs and pathways in neurons. To address this problem, in this study, we focused on a recently identified BD-associated but uncharacterized miRNA, miR-1908-5p. We identified and validated its novel target genes including , , , and , which all function in neuronal glutamatergic synapses. Moreover, bioinformatic analyses of human brain expression profiles revealed that the expression levels of miR-1908-5p and its synaptic target genes show an inverse-correlation in many brain regions. In our preliminary experiments, the expression of miR-1908-5p was increased after chronic treatment with valproate but not lithium in control human neural progenitor cells. In contrast, it was decreased by valproate in neural progenitor cells derived from dermal fibroblasts of a BD subject. Together, our results provide new insights into the potential role of miR-1908-5p in the pathogenesis of BD and also propose a hypothesis that neuronal synapses could be a key converging pathway of some BD-associated protein-coding genes and miRNAs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5607/en.2016.25.6.296DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5195815PMC
December 2016

PIF1-Interacting Transcription Factors and Their Binding Sequence Elements Determine the in Vivo Targeting Sites of PIF1.

Plant Cell 2016 06 14;28(6):1388-405. Epub 2016 Jun 14.

Department of Biological Sciences, KAIST, Daejeon 34141, Korea

The bHLH transcription factor PHYTOCHROME INTERACTING FACTOR1 (PIF1) binds G-box elements in vitro and inhibits light-dependent germination in Arabidopsis thaliana A previous genome-wide analysis of PIF1 targeting indicated that PIF1 binds 748 sites in imbibed seeds, only 59% of which possess G-box elements. This suggests the G-box is not the sole determinant of PIF1 targeting. The targeting of PIF1 to specific sites could be stabilized by PIF1-interacting transcription factors (PTFs) that bind other nearby sequence elements. Here, we report PIF1 targeting sites are enriched with not only G-boxes but also with other hexameric sequence elements we named G-box coupling elements (GCEs). One of these GCEs possesses an ACGT core and serves as a binding site for group A bZIP transcription factors, including ABSCISIC ACID INSENSITIVE5 (ABI5), which inhibits seed germination in abscisic acid signaling. PIF1 interacts with ABI5 and other group A bZIP transcription factors and together they target a subset of PIF1 binding sites in vivo. In vitro single-molecule fluorescence imaging confirms that ABI5 facilitates PIF1 binding to DNA fragments possessing multiple G-boxes or the GCE alone. Thus, we show in vivo PIF1 targeting to specific binding sites is determined by its interaction with PTFs and their binding to GCEs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1105/tpc.16.00125DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4944412PMC
June 2016
-->