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1.
Proc Natl Acad Sci U S A ; 121(26): e2322978121, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38900791

RESUMEN

MDGA (MAM domain containing glycosylphosphatidylinositol anchor) family proteins were previously identified as synaptic suppressive factors. However, various genetic manipulations have yielded often irreconcilable results, precluding precise evaluation of MDGA functions. Here, we found that, in cultured hippocampal neurons, conditional deletion of MDGA1 and MDGA2 causes specific alterations in synapse numbers, basal synaptic transmission, and synaptic strength at GABAergic and glutamatergic synapses, respectively. Moreover, MDGA2 deletion enhanced both N-methyl-D-aspartate (NMDA) receptor- and α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor-mediated postsynaptic responses. Strikingly, ablation of both MDGA1 and MDGA2 abolished the effect of deleting individual MDGAs that is abrogated by chronic blockade of synaptic activity. Molecular replacement experiments further showed that MDGA1 requires the meprin/A5 protein/PTPmu (MAM) domain, whereas MDGA2 acts via neuroligin-dependent and/or MAM domain-dependent pathways to regulate distinct postsynaptic properties. Together, our data demonstrate that MDGA paralogs act as unique negative regulators of activity-dependent postsynaptic organization at distinct synapse types, and cooperatively contribute to adjustment of excitation-inhibition balance.


Asunto(s)
Hipocampo , Sinapsis , Transmisión Sináptica , Animales , Sinapsis/metabolismo , Ratones , Hipocampo/metabolismo , Hipocampo/citología , Transmisión Sináptica/fisiología , Neuronas/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Ratones Noqueados , Receptores AMPA/metabolismo , Receptores AMPA/genética , Moléculas de Adhesión Celular Neuronal/metabolismo , Moléculas de Adhesión Celular Neuronal/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Células Cultivadas
3.
Proc Natl Acad Sci U S A ; 121(12): e2313236121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38466837

RESUMEN

Phase separation drives compartmentalization of intracellular contents into various biomolecular condensates. Individual condensate components are thought to differentially contribute to the organization and function of condensates. However, how intermolecular interactions among constituent biomolecules modulate the phase behaviors of multicomponent condensates remains unclear. Here, we used core components of the inhibitory postsynaptic density (iPSD) as a model system to quantitatively probe how the network of intra- and intermolecular interactions defines the composition and cellular distribution of biomolecular condensates. We found that oligomerization-driven phase separation of gephyrin, an iPSD-specific scaffold, is critically modulated by an intrinsically disordered linker region exhibiting minimal homotypic attractions. Other iPSD components, such as neurotransmitter receptors, differentially promote gephyrin condensation through distinct binding modes and affinities. We further demonstrated that the local accumulation of scaffold-binding proteins at the cell membrane promotes the nucleation of gephyrin condensates in neurons. These results suggest that in multicomponent systems, the extent of scaffold condensation can be fine-tuned by scaffold-binding factors, a potential regulatory mechanism for self-organized compartmentalization in cells.


Asunto(s)
Proteínas Portadoras , Proteínas de la Membrana , Proteínas de la Membrana/metabolismo , Proteínas Portadoras/metabolismo , Sinapsis/metabolismo , Termodinámica
4.
J Vet Sci ; 24(3): e41, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37271509

RESUMEN

Competencies are defined as an observable and assessable set of knowledge, skills, and attitudes. Graduation competencies, which are more comprehensive, refer to the required abilities of students to perform on-site work immediately after graduation. As graduation competencies set the goal of education, various countries and institutions have introduced them for new veterinary graduates. The Korean Association of Veterinary Medical Colleges has recently established such competencies to standardize veterinary education and enhance quality levels thereof. The purpose of this study is to describe the process of establishing graduation competencies as well as their implication for veterinary education in Korea. Graduation competencies for veterinary education in Korea comprise 5 domains (animal health care and disease management, one health expertise, communication and collaboration, research and learning, and veterinary professionalism). These are further divided into 11 core competencies, and 33 achievement standards, which were carefully chosen from previous case analyses and nation-wide surveys. Currently, graduation competencies are used as a standard for setting clear educational purposes for both instructors and students. Establishing these competencies further initiated the development of detailed learning outcomes, and of a list of basic veterinary clinical performances and skills, which is useful for assessing knowledge and skills. The establishment of graduation competencies is expected to contribute to the continuous development of Korean veterinary education in many ways. These include curriculum standardization and licensing examination reform, which will eventually improve the competencies of new veterinary graduates.


Asunto(s)
Educación Médica , Educación en Veterinaria , Animales , Curriculum , República de Corea
5.
Curr Opin Neurobiol ; 81: 102728, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37236068

RESUMEN

Postsynaptic GABAergic receptors interact with various membrane and intracellular proteins to mediate inhibitory synaptic transmission. They form structural and/or signaling synaptic protein complexes that perform a variety of postsynaptic functions. In particular, the key GABAergic synaptic scaffold, gephyrin, and its interacting partners govern downstream signaling pathways that are essential for GABAergic synapse development, transmission, and plasticity. In this review, we discuss recent researches on GABAergic synaptic signaling pathways. We also outline the main outstanding issues that need to be addressed in this field and highlight the association of dysregulated GABAergic synaptic signaling with the onset of various brain disorders.


Asunto(s)
Receptores de GABA-A , Sinapsis , Receptores de GABA-A/metabolismo , Sinapsis/fisiología , Transmisión Sináptica/fisiología , Proteínas Portadoras/metabolismo , Plasticidad Neuronal/fisiología
6.
Animals (Basel) ; 12(21)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36359090

RESUMEN

The release of reproductive hormones in the hypothalamic-pituitary-gonadal (HPG) axis is regulated by its upstream regulator, kisspeptin, and influenced by external stresses, including heat stress. Since the effect of heat stress (summer infertility) on hypothalamic kisspeptin expression in domestic sows is not yet understood, the present study attempted to identify changes in kisspeptin expression in different seasons (summer and spring). The high atmospheric temperature in summer decreased the pregnancy rate and litter size and increased stress-related hormones as a chronic stressor to domestic sows. The hypothalamic kisspeptin expression in summer was decreased regardless of the estrus phase and negatively correlated with atmospheric temperature, indicating that high temperature decreased kisspeptin. When the activity of hypothalamic kisspeptin neurons in the follicular phase was assessed using c-Fos staining, a decreased number of kisspeptin neurons coexpressing c-Fos was observed in domestic sows in summer. Accordingly, lower expression of kisspeptin induced decreased levels of HPG axis-related reproductive hormones, such as gonadotropins and estrogen, and fewer large ovarian follicles. In conclusion, the present study demonstrated that reduced kisspeptin expression and its neuronal activity in the hypothalamus under heat stress in summer induced downregulation of the HPG axis and caused summer infertility in domestic sows.

7.
Anim Biosci ; 35(12): 1850-1859, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35507843

RESUMEN

OBJECTIVE: The quantitative reverse transcription polymerase chain reaction (qPCR) is the most accurate and reliable technique for analysis of gene expression. Endogenous reference genes (RGs) have been used to normalize qPCR data, although their expression may vary in different tissues and experimental conditions. Verification of the stability of RGs in selected samples is a prerequisite for reliable results. Therefore, we attempted to identify the most stable RGs in the hypothalamic-pituitary-gonadal (HPG) axis in sows. METHODS: The cycle threshold values of nine commonly used RGs (18S, HPRT1, GAPDH, RPL4, PPIA, B2M, YWHAZ, ACTB, and SDHA) from HPG axis-related tissues in the domestic sows in the different stages of estrus cycle were analyzed using two RG-finding programs, geNorm and Normfinder, to rank the stability of the pool of RGs. In addition, the effect of the most and least stable RGs was examined by normalization of the target gene, gonadotropin-releasing hormone (GnRH), in the hypothalamus. RESULTS: PPIA, HPRT1, and YWHAZ were the most stable RGs in the HPG axis-related tissues in sows regardless of the stages of estrus cycle. In contrast, traditional RGs, including 18S and ACTB, were found to be the least stable under these experimental conditions. In particular, in the normalization of GnRH expression in the hypothalamus against several stable RGs, PPIA, HPRT1, and YWHAZ, could generate significant (p<0.05) elevation of GnRH in the preovulatory phase compared to the luteal phase, but the traditional RGs with the least stability (18S and ACTB) did not show a significant difference between groups. CONCLUSION: These results indicate the importance of verifying RG stability prior to commencing research and may contribute to experimental design in the field of animal reproductive physiology as reference data.

8.
Chem Sci ; 13(4): 955-966, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35211260

RESUMEN

We developed a proximity photo-crosslinking method (Spotlight) with a 4-azido-N-ethyl-1,8-naphthalimide (AzNP) moiety that can be converted to reactive aryl nitrene species using ambient blue light-emitting diode light. Using an AzNP-conjugated HaloTag ligand (VL1), blue light-induced photo-crosslinked products of various HaloTag-conjugated proteins of interest were detected in subcellular spaces in live cells. Chemical or heat stress-induced dynamic changes in the proteome were also detected, and photo-crosslinking in the mouse brain tissue was enabled. Using Spotlight, we further identified the host interactome of SARS-CoV-2 nucleocapsid (N) protein, which is essential for viral genome assembly. Mass analysis of the VL1-crosslinked product of N-HaloTag in HEK293T cells showed that RNA-binding proteins in stress granules were exclusively enriched in the cross-linked samples. These results tell that our method can reveal the interactome of protein of interest within a short distance in live cells.

9.
Biol Psychiatry ; 91(9): 821-831, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35219498

RESUMEN

BACKGROUND: IQSEC3, a gephyrin-binding GABAergic (gamma-aminobutyric acidergic) synapse-specific guanine nucleotide exchange factor, was recently reported to regulate activity-dependent GABAergic synapse maturation, but the underlying signaling mechanisms remain incompletely understood. METHODS: We generated mice with conditional knockout (cKO) of Iqsec3 to examine whether altered synaptic inhibition influences hippocampus-dependent fear memory formation. In addition, electrophysiological recordings, immunohistochemistry, and behavioral assays were used to address our question. RESULTS: We found that Iqsec3-cKO induces a specific reduction in GABAergic synapse density, GABAergic synaptic transmission, and maintenance of long-term potentiation in the hippocampal CA1 region. In addition, Iqsec3-cKO mice exhibited impaired fear memory formation. Strikingly, Iqsec3-cKO caused abnormally enhanced activation of ribosomal P70-S6K1-mediated signaling in the hippocampus but not in the cortex. Furthermore, inhibiting upregulated S6K1 signaling by expressing dominant-negative S6K1 in the hippocampal CA1 of Iqsec3-cKO mice completely rescued impaired fear learning and inhibitory synapse density but not deficits in long-term potentiation maintenance. Finally, upregulated S6K1 signaling was rescued by IQSEC3 wild-type, but not by an ARF-GEF (adenosine diphosphate ribosylation factor-guanine nucleotide exchange factor) inactive IQSEC3 mutant. CONCLUSIONS: Our results suggest that IQSEC3-mediated balanced synaptic inhibition in hippocampal CA1 is critical for the proper formation of hippocampus-dependent fear memory.


Asunto(s)
Miedo , Factores de Intercambio de Guanina Nucleótido , Hipocampo , Sinapsis , Animales , Factores de Intercambio de Guanina Nucleótido/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Hipocampo/metabolismo , Potenciación a Largo Plazo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Sinapsis/metabolismo , Regulación hacia Arriba
10.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35074912

RESUMEN

Balanced synaptic inhibition, controlled by multiple synaptic adhesion proteins, is critical for proper brain function. MDGA1 (meprin, A-5 protein, and receptor protein-tyrosine phosphatase mu [MAM] domain-containing glycosylphosphatidylinositol anchor protein 1) suppresses synaptic inhibition in mammalian neurons, yet the molecular mechanisms underlying MDGA1-mediated negative regulation of GABAergic synapses remain unresolved. Here, we show that the MDGA1 MAM domain directly interacts with the extension domain of amyloid precursor protein (APP). Strikingly, MDGA1-mediated synaptic disinhibition requires the MDGA1 MAM domain and is prominent at distal dendrites of hippocampal CA1 pyramidal neurons. Down-regulation of APP in presynaptic GABAergic interneurons specifically suppressed GABAergic, but not glutamatergic, synaptic transmission strength and inputs onto both the somatic and dendritic compartments of hippocampal CA1 pyramidal neurons. Moreover, APP deletion manifested differential effects in somatostatin- and parvalbumin-positive interneurons in the hippocampal CA1, resulting in distinct alterations in inhibitory synapse numbers, transmission, and excitability. The infusion of MDGA1 MAM protein mimicked postsynaptic MDGA1 gain-of-function phenotypes that involve the presence of presynaptic APP. The overexpression of MDGA1 wild type or MAM, but not MAM-deleted MDGA1, in the hippocampal CA1 impaired novel object-recognition memory in mice. Thus, our results establish unique roles of APP-MDGA1 complexes in hippocampal neural circuits, providing unprecedented insight into trans-synaptic mechanisms underlying differential tuning of neuronal compartment-specific synaptic inhibition.


Asunto(s)
Precursor de Proteína beta-Amiloide/metabolismo , Hipocampo/metabolismo , Hipocampo/fisiopatología , Moléculas de Adhesión de Célula Nerviosa/genética , Inhibición Neural , Sinapsis/metabolismo , Precursor de Proteína beta-Amiloide/genética , Región CA1 Hipocampal , Proteínas Portadoras , Dendritas/metabolismo , Neuronas GABAérgicas/metabolismo , Interneuronas , Modelos Biológicos , Moléculas de Adhesión de Célula Nerviosa/química , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Inhibición Neural/genética , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Células Piramidales/metabolismo , Receptores de GABA-B/metabolismo , Transmisión Sináptica
11.
J Clin Med ; 10(18)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34575273

RESUMEN

Chronic obstructive pulmonary disease (COPD) is one of the most frequently occurring concomitant diseases in patients with non-small cell lung cancer (NSCLC). It is characterized by small airways and the hyperinflation of the lung. Patients with hyperinflated lung tend to have more reserved lung function than conventionally predicted after lung cancer surgery. The aim of this study was to identify other indicators in predicting postoperative lung function after lung resection for lung cancer. Patients with NSCLC who underwent curative lobectomy with mediastinal lymph node dissection from 2017 to 2019 were included. Predicted postoperative FEV1 (ppoFEV1) was calculated using the formula: preoperative FEV1 × (19 segments-the number of segments to be removed) ÷ 19. The difference between the measured postoperative FEV1 and ppoFEV1 was defined as an outcome. Patients were categorized into two groups: preserved FEV1 if the difference was positive and non-preserved FEV1, if otherwise. In total, 238 patients were included: 74 (31.1%) in the FEV1 non-preserved group and 164 (68.9%) in the FEV1 preserved group. The proportion of preoperative residual volume (RV)/total lung capacity (TLC) ≥ 40% in the FEV1 non-preserved group (21.4%) was lower than in the preserved group (36.1%) (p = 0.03). In logistic regression analysis, preoperative RV/TLC ≥ 40% was related to postoperative FEV1 preservation. (adjusted OR, 2.02, p = 0.041). Linear regression analysis suggested that preoperative RV/TLC was positively correlated with a significant difference. (p = 0.004) Preoperative RV/TLC ≥ 40% was an independent predictor of preserved lung function in patients undergoing curative lobectomy with mediastinal lymph node dissection. Preoperative RV/TLC is positively correlated with postoperative lung function.

12.
Biomed Res Int ; 2021: 4604856, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34527737

RESUMEN

IFN-γ licensing to mesenchymal stem cells (MSCs) is applied to enhance the therapeutic potential of MSCs. However, although the features of MSCs are affected by several stimuli, little information is available on changes to the therapeutic potential of IFN-γ-licensed differentiated MSCs during xenogeneic applications. Therefore, the present study is aimed at clarifying the effects of adipogenic/osteogenic differentiation and IFN-γ licensing on the in vitro immunomodulatory and migratory properties of porcine bone marrow-derived MSCs in xenogeneic applications using human peripheral blood mononuclear cells (PBMCs). IFN-γ licensing in differentiated MSCs lowered lineage-specific gene expression but did not affect MSC-specific cell surface molecules. Although indoleamine 2,3 deoxygenase (IDO) activity and expression were increased after IFN-γ licensing in undifferentiated MSCs, they were reduced after differentiation. IFN-γ licensing to differentiated MSCs elevated the reduced IDO expression in differentiated MSCs; however, the increase was not sufficient to reach to the level achieved by undifferentiated MSCs. During a mixed lymphocyte reaction with quantification of TNF-α concentration, proliferation and activation of xenogeneic PBMCs were suppressed by undifferentiated MSCs but inhibited to a lesser extent by differentiated MSCs. IFN-γ licensing increasingly suppressed proliferation of PBMCs in undifferentiated MSCs but it was incapable of elevating the reduced immunosuppressive ability of differentiated MSCs. Migratory ability through a scratch assay and gene expression study was reduced in differentiated MSCs than their undifferentiated counterparts; IFN-γ licensing was unable to enhance the reduced migratory ability in differentiated MSCs. Similar results were found in a Transwell system with differentiated MSCs in the upper chamber toward xenogeneic PBMCs in the lower chamber, despite IFN-γ licensing increased the migratory ability of undifferentiated MSCs. Overall, IFN-γ licensing did not enhance the reduced immunomodulatory and migratory properties of differentiated MSCs in a xenogeneic application. This study provides a better understanding of the ways in which MSC therapy can be applied.


Asunto(s)
Interferón gamma/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/metabolismo , Animales , Médula Ósea/metabolismo , Células de la Médula Ósea/metabolismo , Diferenciación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Citocinas/metabolismo , Xenoinjertos/metabolismo , Humanos , Inmunomodulación/efectos de los fármacos , Interferón gamma/fisiología , Células Madre Mesenquimatosas/fisiología , Osteogénesis/efectos de los fármacos , Porcinos , Factor de Necrosis Tumoral alfa/metabolismo
13.
Stem Cell Res Ther ; 12(1): 502, 2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34521481

RESUMEN

BACKGROUND: Although the immunomodulatory properties of mesenchymal stem cells (MSCs) have been highlighted as a new therapy for autoimmune diseases, including rheumatoid arthritis (RA), the disease-specific characteristics of MSCs derived from elderly RA patients are not well understood. METHODS: We established MSCs derived from synovial fluid (SF) from age-matched early (average duration of the disease: 1.7 years) and long-standing (average duration of the disease: 13.8 years) RA patients (E-/L-SF-MSCs) and then analyzed the MSC characteristics such as stemness, proliferation, cellular senescence, in vitro differentiation, and in vivo immunomodulatory properties. RESULTS: The presence of MSC populations in the SF from RA patients was identified. We found that L-SF-MSCs exhibited impaired proliferation, intensified cellular senescence, reduced immunomodulatory properties, and attenuated anti-arthritic capacity in an RA animal model. In particular, E-SF-MSCs demonstrated cellular senescence progression and attenuated immunomodulatory properties similar to those of L-SF-MSC in an RA joint-mimetic milieu due to hypoxia and pro-inflammatory cytokine exposure. Due to a long-term exposure to the chronic inflammatory milieu, cellular senescence, attenuated immunomodulatory properties, and the loss of anti-arthritic potentials were more often identified in SF-MSCs in a long-term RA than early RA. CONCLUSION: We conclude that a chronic RA inflammatory milieu affects the MSC potential. Therefore, this work addresses the importance of understanding MSC characteristics during disease states prior to their application in patients.


Asunto(s)
Artritis Reumatoide , Células Madre Mesenquimatosas , Anciano , Animales , Artritis Reumatoide/terapia , Humanos , Inmunomodulación , Lactante , Inflamación , Líquido Sinovial
14.
Cell Rep ; 36(3): 109417, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-34289353

RESUMEN

Activity-dependent GABAergic synapse plasticity is important for normal brain functions, but the underlying molecular mechanisms remain incompletely understood. Here, we show that Npas4 (neuronal PAS-domain protein 4) transcriptionally regulates the expression of IQSEC3, a GABAergic synapse-specific guanine nucleotide-exchange factor for ADP-ribosylation factor (ARF-GEF) that directly interacts with gephyrin. Neuronal activation by an enriched environment induces Npas4-mediated upregulation of IQSEC3 protein specifically in CA1 stratum oriens layer somatostatin (SST)-expressing GABAergic interneurons. SST+ interneuron-specific knockout (KO) of Npas4 compromises synaptic transmission in these GABAergic interneurons, increases neuronal activity in CA1 pyramidal neurons, and reduces anxiety behavior, all of which are normalized by the expression of wild-type IQSEC3, but not a dominant-negative ARF-GEF-inactive mutant, in SST+ interneurons of Npas4-KO mice. Our results suggest that IQSEC3 is a key GABAergic synapse component that is directed by Npas4 and ARF activity, specifically in SST+ interneurons, to orchestrate excitation-to-inhibition balance and control anxiety-like behavior.


Asunto(s)
Ansiedad/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Conducta Animal , Factores de Intercambio de Guanina Nucleótido/metabolismo , Hipocampo/metabolismo , Interneuronas/metabolismo , Somatostatina/metabolismo , Animales , Neuronas GABAérgicas/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Regiones Promotoras Genéticas/genética , Unión Proteica , Sinapsis/metabolismo , Transmisión Sináptica , Regulación hacia Arriba
15.
iScience ; 24(2): 102037, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33532714

RESUMEN

Gephyrin is critical for the structure, function, and plasticity of inhibitory synapses. Gephyrin mutations have been linked to various neurological disorders; however, systematic analyses of the functional consequences of these mutations are lacking. Here, we performed molecular dynamics simulations of gephyrin to predict how six reported point mutations might change the structural stability and/or function of gephyrin. Additional in silico analyses revealed that the A91T and G375D mutations reduce the binding free energy of gephyrin oligomer formation. Gephyrin A91T and G375D displayed altered clustering patterns in COS-7 cells and nullified the inhibitory synapse-promoting effect of gephyrin in cultured neurons. However, only the G375D mutation reduced gephyrin interaction with GABAA receptors and neuroligin-2 in mouse brain; it also failed to normalize deficits in GABAergic synapse maintenance and neuronal hyperactivity observed in hippocampal dentate gyrus-specific gephyrin-deficient mice. Our results provide insights into biochemical, cell-biological, and network-activity effects of the pathogenic G375D mutation.

16.
Asian-Australas J Anim Sci ; 33(12): 2021-2030, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32819081

RESUMEN

OBJECTIVE: Quantitative polymerase chain reaction (qPCR) has been extensively used in the field of mesenchymal stem cell (MSC) research to elucidate their characteristics and clinical potential by normalization of target genes against reference genes (RGs), which are believed to be stably expressed irrespective of various experimental conditions. However, the expression of RGs is also variable depending on the experimental conditions, which may lead to false or contradictory conclusions upon normalization. Due to the current lack of information for a clear list of stable RGs in bovine MSCs, we conducted this study to identify suitable RGs in bovine MSCs. METHODS: The cycle threshold values of ten traditionally used RGs (18S ribosomal RNA [18S], beta-2-microglobulin [B2M], H2A histone family, member Z [H2A], peptidylprolyl isomerase A [PPIA], ribosomal protein 4 [RPL4], succinate dehydrogenase complex, subunit A [SDHA], beta actin [ACTB], glyceraldehyde-3-phosphate dehydrogenase [GAPDH], TATA box binding protein [TBP], and hypoxanthine phosphoribosyltrasnfrase1 [HPRT1]) in bovine bone marrow-derived MSCs (bBMMSCs) were validated for their stabilities using three types of RG evaluation algorithms (geNorm, Normfinder, and Bestkeeper). The effect of validated RGs was then verified by normalization of lineage-specific genes (fatty acid binding protein 4 [FABP4] and osteonectin [ON]) expressions during differentiations of bBMMSCs or POU class 5 homeobox 1 (OCT4) expression between bBMMSCs and dermal skins. RESULTS: Based on the results obtained for the three most stable RGs from geNorm (TBP, RPL4, and H2A), Normfinder (TBP, RPL4, and SDHA), and Bestkeeper (TBP, RPL4, and SDHA), it was comprehensively determined that TBP and RPL4 were the most stable RGs in bBMMSCs. However, traditional RGs were suggested to be the least stable (18S) or moderately stable (GAPDH and ACTB) in bBMMSCs. Normalization of FABP4 or ON against TBP, RPL4, and 18S presented significant differences during differentiation of bBMMSCs. However, although significantly low expression of OCT4 was detected in dermal skins compared to that in bBMMSCs when TBP and RPL4 were used in normalization, normalization against 18S exhibited no significance. CONCLUSION: This study proposes that TBP and RPL4 were suitable as stable RGs for qPCR study in bovine MSCs.

17.
Glia ; 68(12): 2661-2673, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32645240

RESUMEN

IQSEC3, a guanine nucleotide exchange factor for ADP-ribosylation factors (ARF-GEFs) is specifically expressed at GABAergic synapses, and its loss increases seizure susceptibility in mice. However, the contribution of microglia to initiation and/or progression of seizures in IQSEC3-deficient mice has not been investigated. In the current study, we show that mice with hippocampal dentate gyrus (DG)-specific IQSEC3 knockdown (KD) exhibit microglial activation and death of DG granule cell. Furthermore, treatment of IQSEC3-KD mice with minocycline, an inhibitor of microglial activation, blocks DG granule neuron cell death and the occurrence of spontaneous seizures without affecting GABAergic synapse deficits or loss of somatostatin. Our results suggest that microglial activation is involved in a subset of IQSEC3-KD-induced epileptogenesis stages, and that its regulation could be an alternative strategy for managing epilepsy.


Asunto(s)
Microglía , Convulsiones , Animales , Giro Dentado , Factores de Intercambio de Guanina Nucleótido , Hipocampo , Ratones , Neuronas , Sinapsis
18.
Cell Rep ; 30(6): 1995-2005.e5, 2020 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-32049026

RESUMEN

Gephyrin interacts with various GABAergic synaptic proteins to organize GABAergic synapse development. Among the multitude of gephyrin-binding proteins is IQSEC3, a recently identified component at GABAergic synapses that acts through its ADP ribosylation factor-guanine nucleotide exchange factor (ARF-GEF) activity to orchestrate GABAergic synapse formation. Here, we show that IQSEC3 knockdown (KD) reduced GABAergic synaptic density in vivo, suggesting that IQSEC3 is required for GABAergic synapse maintenance in vivo. We further show that IQSEC3 KD in the dentate gyrus (DG) increases seizure susceptibility and triggers selective depletion of somatostatin (SST) peptides in the DG hilus in an ARF-GEP activity-dependent manner. Strikingly, selective introduction of SST into SST interneurons in DG-specific IQSEC3-KD mice reverses GABAergic synaptic deficits. Thus, our data suggest that IQSEC3 is required for linking gephyrin-GABAA receptor complexes with ARF-dependent pathways to prevent aberrant, runaway excitation and thereby contributes to the integrity of SST interneurons and proper GABAergic synapse maintenance.


Asunto(s)
Factores de Intercambio de Guanina Nucleótido/deficiencia , Factores de Intercambio de Guanina Nucleótido/metabolismo , Hipocampo/metabolismo , Proteínas de la Membrana/metabolismo , Somatostatina/metabolismo , Sinapsis/metabolismo , Animales , Células HEK293 , Hipocampo/citología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL
19.
Chem Commun (Camb) ; 56(10): 1549-1552, 2020 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-31930244

RESUMEN

In accordance with the rapid increase in demand for selective and spatial chemical tagging, and accurate detection of proteins of interest, we develop a sensitive protein detection method, termed "Supra-blot" capitalizing on high-affinity host-guest interaction between cucurbit[7]uril (CB[7]) and adamantylammonium (AdA). The method can directly detect chemically tagged proteins without false-positive signals caused by endogenous biomolecules. Not only a single specific protein, but also spatially localized proteins in cells were labeled with AdA, and selectively detected by a host molecule-enzyme hybrid, CB[7]-conjugated horseradish peroxidase (CB[7]-HRP) generating amplified chemiluminescence signals. This study shows the great potential of Supra-blot for accurate and reliable detection of proteins of interest in cells.


Asunto(s)
Hidrocarburos Aromáticos con Puentes/química , Peroxidasa de Rábano Silvestre/química , Imidazoles/química , Mediciones Luminiscentes/métodos , Amantadina/química , Compuestos de Amonio/química , Células HEK293 , Histonas/química , Histonas/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Humanos
20.
Org Lett ; 20(17): 5327-5331, 2018 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-30110171

RESUMEN

A new mode of catalysis of the semipinacol rearrangement of 2,3-epoxy alcohols is described. In combination with a halide salt additive, diarylborinic acids promote a Type II rearrangement that occurs with net retention of configuration. This unusual stereochemical outcome is consistent with a mechanism involving regioselective ring opening of the epoxy alcohol by halide, followed by rearrangement of the resulting halohydrin-derived borinic ester. The protocol is applicable to a range of substrates, enabling ring contractions and expansions as well as stereospecific syntheses of acyclic ß-hydroxycarbonyl compounds.

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