Search results for "ZEBRAFISH"

Genome-wide Trans-ethnic Meta-analysis Identifies Seven Genetic Loci Influencing Erythrocyte Traits and a Role for RBPMS in Erythropoiesis

2017

Genome-wide association studies (GWASs) have identified loci for erythrocyte traits in primarily European ancestry populations. We conducted GWAS meta-analyses of six erythrocyte traits in 71,638 individuals from European, East Asian, and African ancestries using a Bayesian approach to account for heterogeneity in allelic effects and variation in the structure of linkage disequilibrium between ethnicities. We identified seven loci for erythrocyte traits including a locus (RBPMS/GTF2E2) associated with mean corpuscular hemoglobin and mean corpuscular volume. Statistical fine-mapping at this locus pointed to RBPMS at this locus and excluded nearby GTF2E2. Using zebrafish morpholino to evaluat…

Mitochondrial Fatty Acid β-Oxidation Inhibition Promotes Glucose Utilization and Protein Deposition through Energy Homeostasis Remodeling in Fish.

2020

BACKGROUND: Fish cannot use carbohydrate efficiently and instead utilize protein for energy supply, thus limiting dietary protein storage. Protein deposition is dependent on protein turnover balance, which correlates tightly with cellular energy homeostasis. Mitochondrial fatty acid β-oxidation (FAO) plays a crucial role in energy metabolism. However, the effect of remodeled energy homeostasis caused by inhibited mitochondrial FAO on protein deposition in fish has not been intensively studied. OBJECTIVES: This study aimed to identify the regulatory role of mitochondrial FAO in energy homeostasis maintenance and protein deposition by studying lipid, glucose, and protein metabolism in fish. M…

Effect of different oxidative stress degrees generated by hydrogen peroxide on motility and DNA fragmentation of zebrafish (Danio rerio) spermatozoa.

2018

An increase in reactive oxygen species (ROS) or decrease in antioxidant barriers can provoke lipid peroxidation of the membranes or DNA damage of the spermatozoa. The aim of this work is to study the effect of the different degrees of oxidative stress generated by H2 O2 incubation on total motility, kinetics, and DNA fragmentation of zebrafish (Danio rerio) spermatozoa. For this process, experimental groups were incubated in 50 µM (Low; L) and 200 µM (High; H) H2 O2 , respectively, for 20 min at 4oC. Sperm motility parameters were obtained with a computer-assisted sperm analysis (CASA) system. Sperm DNA fragmentation (SDF) was assessed using the sperm chromatin dispersion test. Both low and…

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_…