Zinc transporter expression in zebrafish (Danio rerio) during development

Department of Nutrition and Exercise Sciences, 103 Milam Hall, Oregon State University, Corvallis, OR 97331, USA.
Comparative Biochemistry and Physiology Part C Toxicology & Pharmacology (Impact Factor: 2.3). 05/2011; 155(1):26-32. DOI: 10.1016/j.cbpc.2011.05.002
Source: PubMed


Zinc is a micronutrient important in several biological processes including growth and development. We have limited knowledge on the impact of maternal zinc deficiency on zinc and zinc regulatory mechanisms in the developing embryo due to a lack of in vivo experimental models that allow us to directly study the effects of maternal zinc on embryonic development following implantation. To overcome this barrier, we have proposed to use zebrafish as a model organism to study the impact of zinc during development. The goal of the current study was to profile the mRNA expression of all the known zinc transporter genes in the zebrafish across embryonic and larval development and to quantify the embryonic zinc concentrations at these corresponding developmental time points. The SLC30A zinc transporter family (ZnT) and SLC39A family, Zir-,Irt-like protein (ZIP) zinc transporter proteins were profiled in zebrafish embryos at 0, 2, 6, 12, 24, 48 and 120 h post fertilization to capture expression patterns from a single cell through full development. We observed consistent embryonic zinc levels, but differential expression of several zinc transporters across development. These results suggest that zebrafish is an effective model organism to study the effects of zinc deficiency and further investigation is underway to identify possible molecular pathways that are dysregulated with maternal zinc deficiency.

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Available from: Robert L Tanguay, Oct 13, 2015
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    • "Quantitative real-time PCR: Embryos (n = 30) were collected in RNAlater (Invitrogen) at noted time points, RNA extraction and qPCR preformed as described previously [7]. Ornithine decarboxylase 1 (odc1) was used as a reference gene for normalization [40]. Odc1 was previously verified as a stably expressed reference gene by Dr. Emily Ho’s lab group (unpublished results) and correspondingly used for their studies [40]. "
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    ABSTRACT: The hepatic α-tocopherol transfer protein (TTP) is required for optimal α-tocopherol bioavailability in humans; mutations in the human TTPA gene result in the heritable disorder ataxia with vitamin E deficiency (AVED, OMIM #277460). TTP is also expressed in mammalian uterine and placental cells and in the human embryonic yolk-sac, underscoring TTP's significance during fetal development. TTP and vitamin E are essential for productive pregnancy in rodents, but their precise physiological role in embryogenesis is unknown. We hypothesize that TTP is required to regulate delivery of α-tocopherol to critical target sites in the developing embryo. We tested to find if TTP is essential for proper vertebrate development, utilizing the zebrafish as a non-placental model. We verify that TTP is expressed in the adult zebrafish and its amino acid sequence is homologous to the human ortholog. We show that embryonic transcription of TTP mRNA increases >7-fold during the first 24 hours following fertilization. In situ hybridization demonstrates that Ttpa transcripts are localized in the developing brain, eyes and tail bud at 1-day post fertilization. Inhibiting TTP expression using oligonucleotide morpholinos results in severe malformations of the head and eyes in nearly all morpholino-injected embryos (88% compared with 5.6% in those injected with control morpholinos or 1.7% in non-injected embryos). We conclude that TTP is essential for early development of the vertebrate central nervous system.
    PLoS ONE 10/2012; 7(10):e47402. DOI:10.1371/journal.pone.0047402 · 3.23 Impact Factor
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    • "Primer sequences are listed in Table 1. The primers for genes (zip1, zip3, zip4, zip6, zip9, zip11, zip13, znt1, znt2, znt4, znt5, znt6, znt7, znt8 and znt9) have been reported previously [55]. "
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    PLoS ONE 08/2012; 7(8):e42939. DOI:10.1371/journal.pone.0042939 · 3.23 Impact Factor
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