scholarly journals Morpholino-Mediated Knockdown of ERα, ERβa, and ERβb mRNAs in Zebrafish (Danio rerio) Embryos Reveals Differential Regulation of Estrogen-Inducible Genes

Endocrinology ◽  
2013 ◽  
Vol 154 (11) ◽  
pp. 4158-4169 ◽  
Author(s):  
Lucinda B. Griffin ◽  
Kathleen E. January ◽  
Karen W. Ho ◽  
Kellie A. Cotter ◽  
Gloria V. Callard

Genetically distinct estrogen receptor (ER) subtypes (ERα and ERβ) play a major role in mediating estrogen actions in vertebrates, but their unique and overlapping functions are not entirely clear. Although mammals have 1 gene of each subtype (ESR1 and ESR2), teleost fish have a single esr1 (ERα) and 2 esr2 (ERβa and ERβb) genes. To determine the in vivo role of different ER isoforms in regulating estrogen-inducible transcription targets, zebrafish (Danio rerio) embryos were microinjected with esr-specific morpholino (MO) oligonucleotides to disrupt splicing of the exon III/intron III junction in the DNA-binding domain. Each MO knocked down its respective normal transcript and increased production of variants with a retained intron III (esr1 MO) or a deleted or mis-spliced exon III (esr2a and esr2b MOs). Both esr1 and esr2b MOs blocked estradiol induction of vitellogenin and ERα mRNAs, predominant hepatic genes, but esr2b was the only MO that blocked induction of cytochrome P450 aromatase B mRNA, a predominant brain gene. Knockdown of ERβa with the esr2a MO had no effect on estrogen induction of the 3 mRNAs but, when coinjected with esr1 MO, attenuated the effect of ERα knockdown. Results indicate that ERα and ERβb, acting separately or cooperatively on specific gene targets, are positive transcriptional regulators of estrogen action, but the role of ERβa, if any, is unclear. We conclude that MO technology in zebrafish embryos is an advantageous approach for investigating the interplay of ER subtypes in a true physiological context.

Author(s):  
Noor Izati Abd Aziz ◽  
Vikneswari Perumal ◽  
Suganya Murugesu ◽  
Qamar Uddin Ahmed ◽  
Bisha Fathamah Uzir ◽  
...  

 The use of zebrafish vertebrate model in vivo analysis of the drug toxicity and efficacy, chemical toxicity, and safety is increasing in recent researches. Momordica charantia Linn (Cucurbitaceae) has been traditionally claimed for its many protective roles. However, the development of toxicity effect may cause morphological abnormalities by using an embryo of zebrafish (Danio Rerio) is unknown. Hence, this study was designed to determine the toxicity and teratogenic effect of hydroethanolic extract of M. charantia fruit using Zebrafish (Danio Rerio) embryos. The crude extract was prepared from the fruit of M. charantia using 80% hydroethanolic solvent. The zebrafish embryos were exposed to serial dilution of crude extract. The active constituent was analyzed using gas chromatography coupled with mass spectrophotometry (GC-MS) Momordica charantia Linn (Cucurbitaceae) has been widely commercialized based on traditional usage as an antidiabetic product. The current study has shown the toxic effects of the M.  charantia fruit extract on the developing zebrafish embryos, and the median lethal concentration (LC50) was calculated to be 725.90 mg/L at 48 hpt. The observed effects are dependent on the time of exposure and concentrations of the extract. At higher concentration, the extract causes some morphological defects such as less pigmentation, dented tail, spinal curvature, oedema, reduced hatchability, and growth retardation, that indicates the presence of toxicant(s). Based on the GC-MS profiling, some of the compounds identified in the hydroethanolic extract, such as propanedioic acid and glutamine, may have caused the teratogenic effects to the embryos. Further research on the M. charantia fruit's metabolites should be carried out prior to any nutraceutical or pharmaceutical application.


Blood ◽  
2009 ◽  
Vol 114 (8) ◽  
pp. 1655-1657 ◽  
Author(s):  
Claudio Graziano ◽  
Simona Carone ◽  
Emanuele Panza ◽  
Flora Marino ◽  
Pamela Magini ◽  
...  

Abstract Hereditary thrombocythemia is a rare autosomal dominant disorder caused by mutations in either the thrombopoietin gene (TPO) or its receptor c-MPL. TPO mutations described so far lead to thrombopoietin overproduction through increased translation of m-RNA. Unilateral transverse reduction limb defects are usually sporadic and generally thought to be caused by vascular disruptions. Reports of inherited unilateral limb defects are extremely rare. In the present study, we describe a family with segregation of G185T TPO mutation in the 5′ UTR region in 4 subjects with thrombocythemia. Three of these patients also present congenital transverse limb defects. Association of these events gives a strong hint of the in vivo involvement of thrombopoietin in vasculogenesis, confirming the role of TPO in human development of the hemangioblast, the embryonic progenitor of the hematopoietic and endothelial lineages. This is the first report showing that vascular disruptions could be secondary to specific gene derangements.


2020 ◽  
Vol MA2020-01 (27) ◽  
pp. 1923-1923
Author(s):  
Aaditya Sunil Deshpande ◽  
Eduard Dumitrescu ◽  
Cassandra Orr ◽  
Kenneth Wallace ◽  
Silvana Andreescu

2021 ◽  
Vol MA2021-01 (56) ◽  
pp. 1459-1459
Author(s):  
Aaditya Deshpande ◽  
Eduard Dumitrescu ◽  
Cassandra Orr ◽  
Kenneth Wallace ◽  
Emanuela Andreescu

2006 ◽  
Vol 26 (24) ◽  
pp. 9291-9301 ◽  
Author(s):  
Chantal Beekman ◽  
Massimo Nichane ◽  
Sarah De Clercq ◽  
Marion Maetens ◽  
Thomas Floss ◽  
...  

ABSTRACT Nucleostemin (NS) is a putative GTPase expressed preferentially in the nucleoli of neuronal and embryonic stem cells and several cancer cell lines. Transfection and knockdown studies indicated that NS controls the proliferation of these cells by interacting with the p53 tumor suppressor protein and regulating its activity. To assess the physiological role of NS in vivo, we generated a mutant mouse line with a specific gene trap event that inactivates the NS allele. The corresponding NS −/− embryos died around embryonic day 4. Analyses of NS mutant blastocysts indicated that NS is not required to maintain pluripotency, nucleolar integrity, or survival of the embryonic stem cells. However, the homozygous mutant blastocysts failed to enter S phase even in the absence of functional p53. Haploid insufficiency of NS in mouse embryonic fibroblasts leads to decreased cell proliferation. NS also functions in early amphibian development to control cell proliferation of neural progenitor cells. Our results show that NS has a unique ability, derived from an ancestral function, to control the proliferation rate of stem/progenitor cells in vivo independently of p53.


2016 ◽  
Vol 311 (6) ◽  
pp. R1262-R1270 ◽  
Author(s):  
Velislava Tzaneva ◽  
Steve F. Perry

Carbon monoxide (CO) is a gaseous signaling molecule and is produced in vivo from the intracellular breakdown of heme via the heme oxygenase (HO) family of enzymes. In this study we investigated the role of the HO-1/CO system in the control of ventilation in zebrafish, Danio rerio. Immunohistochemistry revealed the presence of HO-1 in the chemoreceptive neuroepithelial cells (NECs) of larvae (4 days postfertilization) and adults, indicating the potential for endogenous CO production in the NECs. Hypoxia (20 min, water Po2 of 30 mmHg) caused a significant increase in HO-1 activity in whole larvae and in the gills of adult fish. Zebrafish with reduced HO-1 activity (via HO-1 knockdown in larvae or zinc protoporphyrin IX treatment in adults) exhibited increased ventilation frequency ( Vf) under normoxic but not hypoxic conditions. The addition of exogenous CO restored resting Vf in fish with diminished CO production, and in some cases (e.g., hypoxic sham larvae) CO modestly reduced Vf below resting levels. Larval fish were treated with phenylhydrazine (PHZ) to eliminate the potential confounding effects of CO-hemoglobin interactions that might influence ventilation. PHZ treatment did not cause changes in Vf of normoxic larvae, and the addition of CO to PHZ-exposed larvae resulted in a significant decrease in sham and HO-1-deficient fish under normoxic conditions. This study demonstrates for the first time that CO plays an inhibitory role in the control of breathing in larval and adult zebrafish.


2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Konstantin V. Zolotarev ◽  
Valentina N. Kashirtseva ◽  
Alexey V. Mishin ◽  
Natalya F. Belyaeva ◽  
Natalya V. Medvedeva ◽  
...  

Quantum dots (QDs) are nanosized semiconductor crystals. They are currently applied in different science fields such as medicine, namely, cancer diagnostics and treatment. QD toxicity is caused by the toxicity of their components. In vivo application of QDs requires their toxicity assessment, so the purpose of this work has been the estimation of acute and chronic toxicity of the QDs at Danio rerio embryos and larvae, QDs being composed of CdSe/CdS/ZnS/S,S-dihydrolipoic acid/polyacrylic acid. We have found no QD acute toxicity during 48 hours of QDs action at the embryo up to the concentration of 185 μM Cd. QDs have been found to be toxic only at 5–7 days of action, it shows that QDs act accumulatively. Beside lethality, we have observed different larval development defects, that is, differently localized edemas, lag of development, tail curvature, and swimming bladder malformation. Our experimental data as well as literature data show that toxicity of the quantum dots at Danio rerio embryos and larvae is primarily caused by toxic action of Cd2+ ion which arises from partial dissociation of CdSe and CdS molecules.


2018 ◽  
Vol 115 (37) ◽  
pp. E8660-E8667 ◽  
Author(s):  
Abu Shufian Ishtiaq Ahmed ◽  
Kunzhe Dong ◽  
Jinhua Liu ◽  
Tong Wen ◽  
Luyi Yu ◽  
...  

In response to vascular injury, vascular smooth muscle cells (VSMCs) may switch from a contractile to a proliferative phenotype thereby contributing to neointima formation. Previous studies showed that the long noncoding RNA (lncRNA) NEAT1 is critical for paraspeckle formation and tumorigenesis by promoting cell proliferation and migration. However, the role of NEAT1 in VSMC phenotypic modulation is unknown. Herein we showed that NEAT1 expression was induced in VSMCs during phenotypic switching in vivo and in vitro. Silencing NEAT1 in VSMCs resulted in enhanced expression of SM-specific genes while attenuating VSMC proliferation and migration. Conversely, overexpression of NEAT1 in VSMCs had opposite effects. These in vitro findings were further supported by in vivo studies in which NEAT1 knockout mice exhibited significantly decreased neointima formation following vascular injury, due to attenuated VSMC proliferation. Mechanistic studies demonstrated that NEAT1 sequesters the key chromatin modifier WDR5 (WD Repeat Domain 5) from SM-specific gene loci, thereby initiating an epigenetic “off” state, resulting in down-regulation of SM-specific gene expression. Taken together, we demonstrated an unexpected role of the lncRNA NEAT1 in regulating phenotypic switching by repressing SM-contractile gene expression through an epigenetic regulatory mechanism. Our data suggest that NEAT1 is a therapeutic target for treating occlusive vascular diseases.


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