An innovative continuous flow system for monitoring heavy metal pollution in water using transgenic Xenopus laevis tadpoles.
While numerous detection methods exist for environmental heavy metal monitoring, easy-to-use technologies combining rapidity with in vivo measurements are lacking. Multiwell systems exploiting transgenic tadpoles are ideal but require time-consuming placement of individuals in wells. We developed a real-time flow-through system, based on Fountain Flow cytometry, which measures in situ contaminant-induced fluorescence in transgenic amphibian larvae immersed in water samples. The system maintains the advantages of transgenic amphibians, but requires minimal human intervention. Portable and self-contained, it allows on-site measurements. Optimization exploited a transgenic Xenopus laevis bearing a chimeric gene with metal responsive elements fused to eGFP. The transgene was selectively induced by 1 microM Zn(2+). Using this tadpole we show the continuous flow method to be as rapid and sensitive as image analysis. Flow-through readings thus accelerate the overall process of data acquisition and render fluorescent monitoring of tadpoles suitable for on-site tracking of heavy metal pollution.
Fini
Jean-Baptiste
JB
UMR CNRS 7221, Evolution des Regulations Endocriniennes, Departement Regulations, Developpement et Diversite Moleculaire, Museum National d'Histoire Naturelle, 75231 Paris, France.
Pallud-Mothré
Sophie
S
Le Mével
Sébastien
S
Palmier
Karima
K
Havens
Christopher M
CM
Le Brun
Matthieu
M
Mataix
Vincent
V
Lemkine
Gregory F
GF
Demeneix
Barbara A
BA
Turque
Nathalie
N
Johnson
Paul E
PE
D000818:Animals; D030801:Animals, Genetically Modified; D004784:Environmental Monitoring / Q000379:methods*; D005453:Fluorescence; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007814:Larva / Q000166:cytology / Q000187:drug effects; D008668:Metallothionein / Q000378:metabolism; D019216:Metals, Heavy / Q000032:analysis*; D015203:Reproducibility of Results; D020218:Response Elements / Q000235:genetics; D013963:Thyroid Hormones / Q000494:pharmacology; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014876:Water Pollution / Q000032:analysis*; D014982:Xenopus laevis / Q000235:genetics*; D015032:Zinc / Q000032:analysis
D019216:Metals, Heavy; D013963:Thyroid Hormones; D014874:Water Pollutants, Chemical; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D008668:Metallothionein; D015032:Zinc