Neurofibromatosis type 2 (NF-2) is a dominantly inherited genetic disorder that results from variants in the tumor suppressor gene, neurofibromin 2 (NF2). Here, we report the generation of a conditional zebrafish model of neurofibromatosis established by inducible genetic knockout of nf2a/b, the zebrafish homologs of human NF2. Analysis of nf2a and nf2b expression revealed ubiquitous expression of nf2b in the early embryo, with overlapping expression in the neural crest and its derivatives and in the cranial mesenchyme. In contrast, nf2a displayed lower expression levels. Induction of nf2a/b knockout at early stages increased the proliferation of larval Schwann cells and meningeal fibroblasts. Subsequently, in adult zebrafish, nf2a/b knockout triggered the development of a spectrum of tumors, including vestibular Schwannomas, spinal Schwannomas, meningiomas and retinal hamartomas, mirroring the tumor manifestations observed in patients with NF-2. Collectively, these findings highlight the generation of a novel zebrafish model that mimics the complexities of the human NF-2 disorder. Consequently, this model holds significant potential for facilitating therapeutic screening and elucidating key driver genes implicated in NF-2 onset.

• MeSH
• dánio pruhované * genetika   embryologie   MeSH
• geneticky modifikovaná zvířata MeSH
• genový knockout * MeSH
• larva metabolismus   MeSH
• lidé MeSH
• modely nemocí na zvířatech * MeSH
• neurofibromatóza 2 genetika   patologie   metabolismus   MeSH
• neurofibromatózy genetika   patologie   metabolismus   MeSH
• neurofibromin 2 * genetika   metabolismus   nedostatek   MeSH
• proliferace buněk MeSH
• proteiny dánia pruhovaného * genetika   metabolismus   nedostatek   MeSH
• Schwannovy buňky metabolismus   patologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

[Figure: see text].

• MeSH
• biologická evoluce MeSH
• buněčné linie MeSH
• cytokineze * MeSH
• dánio pruhované MeSH
• endozomální třídící komplexy pro transport metabolismus   MeSH
• fosfatidylinositol-3-kinasy genetika   metabolismus   MeSH
• fosfatidylinositol-4,5-difosfát metabolismus   MeSH
• fosfatidylinositoly metabolismus   MeSH
• katarakta metabolismus   patologie   MeSH
• lidé MeSH
• mutace MeSH
• myši MeSH
• oční čočka cytologie   růst a vývoj   metabolismus   MeSH
• předčasné stárnutí MeSH
• proteiny buněčného cyklu metabolismus   MeSH
• proteiny dánia pruhovaného genetika   metabolismus   MeSH
• proteiny vázající vápník metabolismus   MeSH
• stárnutí buněk * MeSH
• tubulin metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

The 14-3-3 proteins constitute a family of adaptor proteins with many binding partners and biological functions, and they are considered promising drug targets in cancer and neuropsychiatry. By screening 1280 small-molecule drugs using differential scanning fluorimetry (DSF), we found 15 compounds that decreased the thermal stability of 14-3-3ζ Among these compounds, ebselen was identified as a covalent, destabilizing ligand of 14-3-3 isoforms ζ, ε, γ, and η Ebselen bonding decreased 14-3-3ζ binding to its partner Ser19-phosphorylated tyrosine hydroxylase. Characterization of site-directed mutants at cysteine residues in 14-3-3ζ (C25, C94, and C189) by DSF and mass spectroscopy revealed covalent modification by ebselen of all cysteines through a selenylsulfide bond. C25 appeared to be the preferential site of ebselen interaction in vitro, whereas modification of C94 was the main determinant for protein destabilization. At therapeutically relevant concentrations, ebselen and ebselen oxide caused decreased 14-3-3 levels in SH-SY5Y cells, accompanied with an increased degradation, most probably by the ubiquitin-dependent proteasome pathway. Moreover, ebselen-treated zebrafish displayed decreased brain 14-3-3 content, a freezing phenotype, and reduced mobility, resembling the effects of lithium, consistent with its proposed action as a safer lithium-mimetic drug. Ebselen has recently emerged as a promising drug candidate in several medical areas, such as cancer, neuropsychiatric disorders, and infectious diseases, including coronavirus disease 2019. Its pleiotropic actions are attributed to antioxidant effects and formation of selenosulfides with critical cysteine residues in proteins. Our work indicates that a destabilization of 14-3-3 may affect the protein interaction networks of this protein family, contributing to the therapeutic potential of ebselen. SIGNIFICANCE STATEMENT: There is currently great interest in the repurposing of established drugs for new indications and therapeutic targets. This study shows that ebselen, which is a promising drug candidate against cancer, bipolar disorder, and the viral infection coronavirus disease 2019, covalently bonds to cysteine residues in 14-3-3 adaptor proteins, triggering destabilization and increased degradation in cells and intact brain tissue when used in therapeutic concentrations, potentially explaining the behavioral, anti-inflammatory, and antineoplastic effects of this drug.

• MeSH
• buněčné linie MeSH
• cirkulární dichroismus MeSH
• cystein genetika   MeSH
• dánio pruhované MeSH
• down regulace MeSH
• isoindoly farmakologie   MeSH
• konformace proteinů MeSH
• lidé MeSH
• molekulární modely MeSH
• mozek metabolismus   MeSH
• mutageneze cílená MeSH
• organoselenové sloučeniny farmakologie   MeSH
• proteiny 14-3-3 chemie   genetika   metabolismus   MeSH
• proteiny dánia pruhovaného chemie   metabolismus   MeSH
• stabilita proteinů účinky léků   MeSH
• tyrosin-3-monooxygenasa metabolismus   MeSH
• vazba proteinů účinky léků   MeSH
• vazebná místa účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Macrophages derive from multiple sources of hematopoietic progenitors. Most macrophages require colony-stimulating factor 1 receptor (CSF1R), but some macrophages persist in the absence of CSF1R. Here, we analyzed mpeg1:GFP-expressing macrophages in csf1r-deficient zebrafish and report that embryonic macrophages emerge followed by their developmental arrest. In larvae, mpeg1+ cell numbers then increased showing two distinct types in the skin: branched, putative Langerhans cells, and amoeboid cells. In contrast, although numbers also increased in csf1r-mutants, exclusively amoeboid mpeg1+ cells were present, which we showed by genetic lineage tracing to have a non-hematopoietic origin. They expressed macrophage-associated genes, but also showed decreased phagocytic gene expression and increased epithelial-associated gene expression, characteristic of metaphocytes, recently discovered ectoderm-derived cells. We further demonstrated that juvenile csf1r-deficient zebrafish exhibit systemic macrophage depletion. Thus, csf1r deficiency disrupts embryonic to adult macrophage development. Zebrafish deficient for csf1r are viable and permit analyzing the consequences of macrophage loss throughout life.

• MeSH
• dánio pruhované embryologie   MeSH
• makrofágy metabolismus   fyziologie   MeSH
• mikroglie metabolismus   fyziologie   MeSH
• proliferace buněk MeSH
• proteiny dánia pruhovaného metabolismus   fyziologie   MeSH
• receptory faktoru stimulujícího granulocyto-makrofágové kolonie metabolismus   fyziologie   MeSH
• stanovení celkové genové exprese MeSH
• tyrosinkinasy metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• audiovizuální média MeSH
• časopisecké články MeSH
• práce podpořená grantem MeSH

The neural crest (NC) is crucial for the evolutionary diversification of vertebrates. NC cells are induced at the neural plate border by the coordinated action of several signaling pathways, including Wnt/β-catenin. NC cells are normally generated in the posterior neural plate border, whereas the anterior neural fold is devoid of NC cells. Using the mouse model, we show here that active repression of Wnt/β-catenin signaling is required for maintenance of neuroepithelial identity in the anterior neural fold and for inhibition of NC induction. Conditional inactivation of Tcf7l1, a transcriptional repressor of Wnt target genes, leads to aberrant activation of Wnt/β-catenin signaling in the anterior neuroectoderm and its conversion into NC. This reduces the developing prosencephalon without affecting the anterior-posterior neural character. Thus, Tcf7l1 defines the border between the NC and the prospective forebrain via restriction of the Wnt/β-catenin signaling gradient.

• MeSH
• beta-katenin metabolismus   MeSH
• biologické markery metabolismus   MeSH
• buněčný rodokmen * MeSH
• crista neuralis cytologie   metabolismus   MeSH
• dánio pruhované metabolismus   MeSH
• defekty neurální trubice metabolismus   patologie   MeSH
• delece genu MeSH
• fenotyp MeSH
• integrasy metabolismus   MeSH
• lidé MeSH
• myši transgenní MeSH
• přední mozek embryologie   metabolismus   MeSH
• protein 1 podobný transkripčnímu faktoru 7 metabolismus   MeSH
• proteiny dánia pruhovaného metabolismus   MeSH
• represorové proteiny metabolismus   MeSH
• signální dráha Wnt MeSH
• transdiferenciace buněk MeSH
• transkripční faktor AP-2 metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Axon guidance relies on precise translation of extracellular signal gradients into local changes in cytoskeletal dynamics, but the molecular mechanisms regulating dose-dependent responses of growth cones are still poorly understood. Here, we show that during embryonic development in growing axons, a low level of Semaphorin3A stimulation is buffered by the prolyl isomerase Pin1. We demonstrate that Pin1 stabilizes CDK5-phosphorylated CRMP2A, the major isoform of CRMP2 in distal axons. Consequently, Pin1 knockdown or knockout reduces CRMP2A levels specifically in distal axons and inhibits axon growth, which can be fully rescued by Pin1 or CRMP2A expression. Moreover, Pin1 knockdown or knockout increases sensitivity to Sema3A-induced growth cone collapse in vitro and in vivo, leading to developmental abnormalities in axon guidance. These results identify an important isoform-specific function and regulation of CRMP2A in controlling axon growth and uncover Pin1-catalyzed prolyl isomerization as a regulatory mechanism in axon guidance.

• MeSH
• axony metabolismus   MeSH
• dánio pruhované MeSH
• fosforylace MeSH
• imunohistochemie MeSH
• imunoprecipitace MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• peptidylprolylisomerasa genetika   metabolismus   MeSH
• proteiny dánia pruhovaného genetika   metabolismus   MeSH
• proteiny nervové tkáně genetika   metabolismus   MeSH
• signální transdukce MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

OBJECTIVES: The aim of this study was to investigate the effects of the nonsteroidal antiinflammatory drug naproxen on adult zebrafish (Danio rerio). METHODS: Three months old zebrafish (Danio rerio) were exposed to naproxen at concentrations of 0.001, 0.1 and 5 mg.L(-1). We focused on the changes in oxidative stress indices during and at the end of the experiment and histopathological examination of tissues after a two week long exposure period. RESULTS: We found that a 3 day long exposure to naproxen causes mild oxidative stress and affects detoxification in zebrafish, which is demonstrated by the increased activity of glutathione peroxidase and glutathione S-transferase at 0.001 and 0.1 mg.L(-1) of naproxen, respectively. After a 7 day long exposure to 0.1 and 5 mg.L(-1), more potent effects on enzymes occur. However, these effects are only short lasting. At the end of the experiment, the activities of the target enzymes recover back to homeostatic baseline levels. Except catalase, which is induced only after a two week long exposure to the environmental concentration of naproxen. Despite the fact that naproxen causes mild oxidative stress in zebrafish, exposure to this drug does not result in lipid peroxidation. Histopathological examination revealed obvious changes to the gills and liver even at exposure to the environmental concentration of naproxen. CONCLUSION: This study demonstrates that the environmental concentration of naproxen can slightly influence both the antioxidant defense system and histopathology of non-target fish.

• MeSH
• antiflogistika nesteroidní farmakologie   MeSH
• chemické znečištění vody MeSH
• dánio pruhované MeSH
• glutathionperoxidasa účinky léků   metabolismus   MeSH
• glutathiontransferasa účinky léků   metabolismus   MeSH
• játra účinky léků   patologie   MeSH
• kůže účinky léků   patologie   MeSH
• ledviny účinky léků   patologie   MeSH
• naproxen farmakologie   MeSH
• oxidační stres účinky léků   MeSH
• peroxidace lipidů účinky léků   MeSH
• proteiny dánia pruhovaného účinky léků   metabolismus   MeSH
• žábry účinky léků   patologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH