Zebrafish model in toxicology

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Zebrafish model in toxicology
Forschungszentrum Karlsruhe in the
Helmholtz-Gemeinschaft

• Uwe Strähle
• Institute of Toxicology and Genetics
• FZK, Karlsruhe and
• University of Heidelberg
• Germany

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Zebrafish embryos as toxicological models
Forschungszentrum Karlsruhe in the
Helmholtz-Gemeinschaft
Zebrafish well-developed embryological system.
Small transparent embryos, development
outside of mother, transgenics,
mutants.... Zebrafish embryos as test system
attract little ethical concerns. Zebrafish
embryo test is DIN-Norm assay in Germany to
evaluate water quality. Zebrafish genetic system
to elucidate toxic mechanism.
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Zebrafish embryos as vertebrate models for DNT
Forschungszentrum Karlsruhe in the
Helmholtz-Gemeinschaft
Zebrafish are ..... ...cheap.
1 to 2 US
ltlt 1cent
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Fluorescent reporters allow monitoring of toxic
action at cellular to subcellular resolution in
the living embryo.
Transgenic embryo expressing GFP under control
of the neural determination gene neurogenin1.
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Forschungszentrum Karlsruhe in the
Helmholtz-Gemeinschaft
Hypothesis Changes in gene expression are more
specific than morphological effects.
------ Toxicogenomics Systematic identification
of molecular markers Can we identify specific
molecular response patterns? Can we identify
markers useful for DNT? ------ Long-term aims
Array based biosensor Novel transgenic reporters
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Forschungszentrum Karlsruhe in the
Helmholtz-Gemeinschaft
Microarray analysis
-expose 300 embryos to toxin (3 stages) -prepare
cDNA 24 hours later -three stages (24 h, 48 h
and 120 h) -hybridize to oligonucleotide array
toxin
toxin
toxin
array
array
array
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Specific toxicogenomic profiles at 5 days
post-fertilisation
Specific toxicogenomic profiles at 5 days
post-fertilisation
Acrylamide
Valproic acid
PCB
4-chloraniline
As2O3
PbCl2
Me-mercury
CdCl2
tBHQ
DDT
TCDD
BDE47
8
mg/l
mg/l
microg/l
ng/l
mg/l
1.5
0.5
250
50
50 25 5 0.5
15
6
500
2.5
0.5
60
30
5
The transcriptional profile responds
to environmental relevant concentrations.
3
-3
DDT
4-chloraniline
Me-Hg
TCDD
CdCl2
9
PCR analysis confirms gene responses in all
selected cases.
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The gene array analysis identified genes whose
expression is restricted to a few cells in the
nervous system
Cadmium
Control
thioredoxin
Control

• Cadmium

Oncomodulin A
Oncomodulin A
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Towards a bar code.
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Forschungszentrum Karlsruhe in the
Helmholtz-Gemeinschaft
Summary

• - Toxins induce specific patterns of gene
  expression.
• Changes in gene expression can be detected
• at low toxin concentration.
• -Gene responses are similar to those seen in
  mammals

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Collaborators
Forschungszentrum Karlsruhe in the
Helmholtz-Gemeinschaft

• Lixin Yang
• Jules Kemadjou
• Matthias Bauer
• Michael Pankratz
• Jens Jäkel
• Christian Zinsmeister