Search results for "ZEBRA"

Flexible multi-beam light-sheet fluorescence microscope for live imaging without striping artifacts

2018

The development of light-sheet fluorescence microscopy (LSFM) has greatly expanded the experimental capabilities in many biological and biomedical research fields, enabling for example live studies of murine and zebrafish neural activity or of cell growth and division. The key feature of the method is the selective illumination of a sample single plane, providing an intrinsic optical sectioning and allowing direct 2D image recording. On the other hand, this excitation scheme is more affected by absorption or scattering artifacts in comparison to point scanning methods, leading to un-even illumination. We present here an easily implementable method, based on acousto-optical deflectors (AOD),…

The Presence or Absence of Intestinal Microbiota Affects Lipid Deposition and Related Genes Expression in Zebrafish (Danio rerio)

2018

Understanding how intestinal microbiota alters energy homeostasis and lipid metabolism is a critical process in energy balance and health. However, the exact role of intestinal microbiota in the regulation of lipid metabolism in fish remains unclear. Here, we used two zebrafish models (germ-free and antibiotics-treated zebrafish) to identify the role of intestinal microbiota in lipid metabolism. Conventional and germ-free zebrafish larvae were fed with egg yolk. Transmission electron microscopy was used to detect the presence of lipid droplets in the intestinal epithelium. The results showed that, microbiota increased lipid accumulation in the intestinal epithelium. The mRNA sequencing tech…

2016

Common birthmarks can be an indicator of underlying genetic disease but are often overlooked. Mongolian blue spots (dermal melanocytosis) are usually localized and transient, but they can be extensive, permanent, and associated with extracutaneous abnormalities. Co-occurrence with vascular birthmarks defines a subtype of phakomatosis pigmentovascularis, a group of syndromes associated with neurovascular, ophthalmological, overgrowth, and malignant complications. Here, we discover that extensive dermal melanocytosis and phakomatosis pigmentovascularis are associated with activating mutations in GNA11 and GNAQ, genes that encode Gα subunits of heterotrimeric G proteins. The mutations were det…

Identification of accessory olfactory system and medial amygdala in the zebrafish

2017

AbstractZebrafish larvae imprint on visual and olfactory cues of their kin on day 5 and 6 postfertilization, respectively. Only imprinted (but not non-imprinted) larvae show strongly activated crypt (and some microvillous) cells demonstrated by pERK levels after subsequent exposure to kin odor. Here, we investigate the olfactory bulb of zebrafish larvae for activated neurons located at the sole glomerulus mdG2 which receives crypt cell input. Imprinted larvae show a significantly increased activation of olfactory bulb cells compared to non-imprinted larvae after exposure to kin odor. Surprisingly, pERK activated Orthopedia-positive cell numbers in the intermediate ventral telencephalic nucl…

Immunohistochemical analysis of NKX2.2, ETV4, and BCOR in a large series of genetically confirmed Ewing sarcoma family of tumors

2017

Ewing sarcoma is an aggressive neoplasm of pediatric and adolescent patients. Immunohistochemistry (IHC) can be used to support the morphologic diagnosis of Ewing sarcoma family of tumors (ESFT) in a convincing clinical/radiological context. Although neither NKX2.2 nor CD99 alone are entirely specific, when combined, the diagnostic specificity is high. The aim of the present study was to investigate the IHC expression of NKX2.2, ETV4 and BCOR in a large series of genetically confirmed ESFT. The results for CD99 and CAV-1 immunoreactivity, and the histological and fusion gene subtypes were retrieved from our previous study. NKX2.2 demonstrated moderate or strong nuclear positivity in 91.2% o…

Active behaviour during early development shapes glucocorticoid reactivity.

2019

AbstractGlucocorticoids are the final effectors of the stress axis, with numerous targets in the central nervous system and the periphery. They are essential for adaptation, yet currently it is unclear how early life events program the glucocorticoid response to stress. Here we provide evidence that involuntary swimming at early developmental stages can reconfigure the cortisol response to homotypic and heterotypic stress in larval zebrafish (Danio rerio), also reducing startle reactivity and increasing spontaneous activity as well as energy efficiency during active behaviour. Collectively, these data identify a role of the genetically malleable zebrafish for linking early life stress with …

Usherin defects lead to early-onset retinal dysfunction in zebrafish

2018

Mutations in USH2A are the most frequent cause of Usher syndrome and autosomal recessive nonsyndromic retinitis pigmentosa. To unravel the pathogenic mechanisms underlying USH2A-associated retinal degeneration and to evaluate future therapeutic strategies that could potentially halt the progression of this devastating disorder, an animal model is needed. The available Ush2a knock-out mouse model does not mimic the human phenotype, because it presents with only a mild and late-onset retinal degeneration. Using CRISPR/Cas9-technology, we introduced protein-truncating germline lesions into the zebrafish ush2a gene (ush2a(rmc1): c.2337_2342delinsAC; p.Cys780GlnfsTer32 and ush2a(b1245): c.15520_…

On the origin of BAG(3) and its consequences for an expansion of BAG3's role in protein homeostasis

2021

The B-cell CLL 2-associated athanogene (BAG) protein family in general and BAG3, in particular, are pivotal elements of cellular protein homeostasis, with BAG3 playing a major role in macroautophagy. In particular, in the contexts of senescence and degeneration, BAG3 has exhibited an essential role often related to its capabilities to organize and remove aggregated proteins. Exciting studies in different species ranging from human, murine, zebrafish, and plant samples have delivered vital insights into BAG3s' (and other BAG proteins') functions and their regulations. However, so far no studies have addressed neither BAG3's evolution nor its phylogenetic position in the BAG family.

Cellular Response to Spinal Cord Injury in Regenerative and Non-Regenerative Stages in Xenopus Laevis

2020

Abstract Background The efficient regenerative abilities at larvae stages followed by a non-regenerative response after metamorphosis in froglets makes Xenopus an ideal model organism to understand the cellular responses leading to spinal cord regeneration. Methods We compared the cellular response to spinal cord injury between the regenerative and non-regenerative stages of Xenopus laevis. For this analysis, we used electron microscopy, immunofluorescence and histological staining of the extracellular matrix. We generated two transgenic lines: i) the reporter line with the zebrafish GFAP regulatory regions driving the expression of EGFP, and ii) a cell specific inducible ablation line with…

Dextran production by Lactobacillus sakei MN1 coincides with reduced autoagglutination, biofilm formation and epithelial cell adhesion

2017

40 p.-7 fig.-4 fig.supl.