Search results for "Oryzias"
showing 10 items of 11 documents
Use of Medaka Fish as Vertebrate Model to Study the Effect of Cocoa Polyphenols in the Resistance to Oxidative Stress and Life Span Extension.
2018
Oxidative stress (OS) can induce cell apoptosis and thus plays an important role in aging. Antioxidant foods protect tissues from OS and contribute to a healthier lifestyle. In this study, we described the used of medaka embryos (Oryzias latipes) to study the putative antioxidant capacity of dietary cocoa extract in vertebrates. A polyphenol-enriched cocoa extract regulated the expression of several genes implicated in OS, thereby protecting fish embryos from induced OS. The cocoa extract activated superoxide dismutase enzyme activity in embryos and adult fish tissues, suggesting a common mechanism for protection during embryonic development and adulthood. Furthermore, long-term feeding of …
iDamIDseq and iDEAR: an improved method and computational pipeline to profile chromatin-binding proteins
2016
DNA adenine methyltransferase identification (DamID) has emerged as an alternative method to profile protein-DNA interactions; however, critical issues limit its widespread applicability. Here, we present iDamIDseq, a protocol that improves specificity and sensitivity by inverting the steps DpnI-DpnII and adding steps that involve a phosphatase and exonuclease. To determine genome-wide protein-DNA interactions efficiently, we present the analysis tool iDEAR (iDamIDseq Enrichment Analysis with R). The combination of DamID and iDEAR permits the establishment of consistent profiles for transcription factors, even in transient assays, as we exemplify using the small teleost medaka (Oryzias lati…
Analysis of the Ush2a Gene in Medaka Fish (Oryzias latipes)
2013
Patients suffering from Usher syndrome (USH) exhibit sensorineural hearing loss, retinitis pigmentosa (RP) and, in some cases, vestibular dysfunction. USH is the most common genetic disorder affecting hearing and vision and is included in a group of hereditary pathologies associated with defects in ciliary function known as ciliopathies. This syndrome is clinically classified into three types: USH1, USH2 and USH3. USH2 accounts for well over one-half of all Usher cases and mutations in the USH2A gene are responsible for the majority of USH2 cases, but also for atypical Usher syndrome and recessive non-syndromic RP. Because medaka fish (Oryzias latypes) is an attractive model organism for ge…
Nanog Regulates Primordial Germ Cell Migration Through Cxcr4b
2010
Abstract Gonadal development in vertebrates depends on the early determination of primordial germ cells (PGCs) and their correct migration to the sites where the gonads develop. Several genes have been implicated in PGC specification and migration in vertebrates. Additionally, some of the genes associated with pluripotency, such as Oct4 and Nanog, are expressed in PGCs and gonads, suggesting a role for these genes in maintaining pluripotency of the germ lineage, which may be considered the only cell type that perpetually maintains stemness properties. Here, we report that medaka Nanog (Ol-Nanog) is expressed in the developing PGCs. Depletion of Ol-Nanog protein causes aberrant migration of …
Nanog Regulates Proliferation During Early Fish Development
2009
Abstract Nanog is involved in controlling pluripotency and differentiation of stem cells in vitro. However, its function in vivo has been studied only in mouse embryos and various reports suggest that Nanog may not be required for the regulation of differentiation. To better understand endogenous Nanog function, more animal models should be introduced to complement the murine model. Here, we have identified the homolog of the mammalian Nanog gene in teleost fish and describe the endogenous expression of Ol-Nanog mRNA and protein during medaka (Oryzias latipes) embryonic development and in the adult gonads. Using medaka fish as a vertebrate model to study Nanog function, we demonstrate that …
Mn(II) complexes of scorpiand-like ligands. A model for the MnSOD active centre with high in vitro and in vivo activity
2015
Manganese complexes of polyamines consisting of an aza-pyridinophane macrocyclic core functionalised with side chains containing quinoline or pyridine units have been characterised by a variety of solution techniques and single crystal x-ray diffraction. Some of these compounds have proved to display interesting antioxidant capabilities in vitro and in vivo in prokaryotic (bacteria) and eukaryotic (yeast and fish embryo) organisms. In particular, the Mn complex of the ligand containing a 4-quinoline group in its side arm which, as it happens in the MnSOD enzymes, has a water molecule coordinated to the metal ion that shows the lowest toxicity and highest functional efficiency both in vitro …
H-Y antigen in the teleost.
1979
H-Y antigen, presumably the product of mammalian testis-determining genes, has been detected in three species of teleost fish, Xiphophorus maculatus, Haplochromis burtoni, and Oryzias latipes, and in hybrids of the genus Tilapia. In X. maculatus H-Y was most readily detected in YY males, suggesting that a genetic determinant of H-Y antigen expression may exist on the teleost Y-chromosome. Although H-Y was detected in males and not in females in each of the species that we studied, male heterogamety has not been firmly established for H. burtoni. Thus despite the extreme phlyogenetic conservation of H-Y genes and their association with the Y-chromosome, it remains open to question whether H-…
Isolation and characterization of cold-shock domain protein genes, Oryzias latipes Y-box protein 2 ( OlaYP2 ) and Fugu rubripes Y-box protein 1 ( Fru…
2002
The Y-box protein (YP) family shares a nucleic acid binding domain, called cold-shock domain, that has been evolutionarily highly conserved from bacteria to human. The different YPs identified so far in vertebrates are thought to function as transcriptional activators, transcriptional repressors and/or translational repressors. Medakafish and pufferfish are very suitable vertebrate models for the study of developmental genetics and comparative genomics, respectively. Here we report the isolation of two teleost YP genes, medakafish Oryzias latipes (Ola)YP2 and Fugu rubripes (Fru)YP1, which are expressed in multiple tissues. Phylogenetic analysis demonstrated that OlaYP2 and FruYP1 belong to …
Duplicated cytoglobin genes in teleost fishes
2005
Cytoglobin is a recently discovered myoglobin-related O2-binding protein of vertebrates with uncertain function. It occurs as single-copy gene in mammals. Here, we demonstrate the presence of two paralogous cytoglobin genes (Cygb-1 and Cygb-2) in the teleost fishes Danio rerio, Oryzias latipes, Tetraodon nigroviridis, and Takifugu rubripes. The globin-typical introns at positions B12.2 and G7.0 are conserved in both genes, whereas the C-terminal exon found in mammalian cytoglobin is absent in the fish genes. Phylogenetic analyses show that the two cytoglobin genes diverged early in teleost evolution. This is confirmed by gene synteny analyses, which suggest a large-scale duplication event. …
Cytochrome P450 1A- and stress protein-induction in early life stages of medaka (Oryzias latipes) exposed to trichloroethylene (TCE) soot and differe…
2013
It has previously been shown that trichloroethylene (TCE) soot extracts cause dioxinlike toxic effects in medaka fish (Oryzias latipes) and primary liver cell culture of rainbow trout (Oncorhynchus mykiss). This study examines embryonic and larval induction of cytochrome P450 1A and stress proteins after exposure of medaka embryos to extracts and fractions of TCE combustien-generated aerosols. Embryos were exposed to three concentrations of whole soot extract (WE; 2.7, 7.2 and 18 μg l -1 incomplete combustion by-products), TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin, 3 ng l -1 ) and four TCE fractions with different polarity (Fr 1-4; 18 μg l -1 ) for 8 days. Approximately 50% of the embryos w…