TABLE CONTENTS

A Subtracted cDNA Library of Putative Chromium Influenced Genes: A
Nematode Generated Resource in Ecotoxicology
Boyle, S. & T. Kakouli-Duarte
Molecular Ecology and Nematode Research Group, Department of Science and Health, Institute of Technology
Carlow, Kilkenny Road, Carlow, Ireland.
Nematodes constitute the most numerous phylum on the planet and are a valuable resource in
determining the health of an environment. Covering wide ranging and diverse habitats, they
have adapted to feed on almost any available food source. Therefore, they can be affected by
and reflect food chain contamination at many levels.
The entomopathogenic nematode (EPN) Steinernema feltiae is ubiquitous in Ireland, and it
can be easily isolated from the soils and cultured in the laboratory. At the Institute of
Technology Carlow we have been investigating this nematode as a bioindicator for the
contamination of soils with hexavalent chromium (chromiumVI). Subsequently, we have
discovered that the nematode demonstrates considerable resistance to this chemical at high
concentrations and that there appear to be tangible molecular effects associated with exposure
to chromium VI. Chromium is a widely documented carcinogen affecting a wide variety of
organisms including humans. It is widely used in industrial activities and is often disposed off
inappropriately leading to environmental contamination.
Consequently, we have begun to develop a subtracted cDNA library that will contain genes
expressed in S. feltiae in the presence of chromium VI. We envisage that this library will lead
to the development of useful and reliable molecular markers that can be employed in the field
as detectors of chromium induced molecular damage. This in turn will yield information
about the levels of contamination and its effects in the ecosystem. In addition, this resource
can be developed further with the development of ‘universal’ PCR-based molecular probes
that can retrieve homologous genes from other organisms for similar purposes.
5 th International Congress of Nematology, 2008 91