Photomicrograph of injecting
a zebrafish embryo
Making of a transgenic fish. Pollution responsive
reporter genes are microinjected into one-celled
fish embryos shortly after fertilization.
The functional gene is incorporated into
the genome of a small portion of the injected
fish, and the degree to which it mimics
native gene expression is determined.
Representation of our transgenic fish sentinel for biological monitoring. Transgenic zebrafish with pollution responsive DNA elements are placed in a body of water. The contaminants bioconcentrate 1,000- to 100,000-fold in the tissues of the fish, activating the response elements (RE) that induce the production of luciferase. This assay does not require killing the fish and allows for repeated analysis of the same site with the same fish.
Municipal drinking water systems are potential
targets for terrorists and are vulnerable
to both intentional and accidental contamination. Intentional
contamination could result from direct introduction
of a toxic chemical into a drinking water
system, or intentional destruction of a structure,
that causes chemical contamination of the
distribution systems for drinking water
are the most vulnerable and deliver their
product directly to numerous homes and
workplaces. This transgenic sentinel can
monitor these vulnerable systems by detecting
biologically significant doses of innumerable
our laboratory we have assayed 18 potential
environmental chemical contaminants, including
biological warfare agents such as parathion
and paraoxon (chemical relatives of sarin).
We will generate lines of transgenic zebrafish
biomonitors by introducing an easily assayable
reporter gene under the control of pollution
responsive DNA elements. The final product
of this project will be a sentinel for
biological monitoring of environmental
pollution capable of recognizing toxic
chemicals within a complex environmental
mixture, using an easily assayable reporter
gene in live fish.