|John M. Clark
Professor of Veterinary and Animal Sciences, University of Massachusetts
Ph.D.: Michigan State University
Molecular Action of Pesticides and Cellular Basis for Resistance
My research program addresses a number of issues broadly defined as pesticide toxicology. In our attempts to evaluate the toxic action of pesticides on target organisms, we have elucidated many fundamental physiological processes and recently began the study of these interactions at the molecular level. Given the effectiveness and widespread use of pesticides, it was probably naive not to have envisioned the environmental concerns that the use of these chemicals has caused. Nevertheless, the negative aspects of pesticides and their use have resulted in a much more complete and rigorous understanding of how they locate and bind target molecules, their environmental fate and degradation, and problems associated with extensive overuse, such as resistance. Thus, the most enduring contribution of pesticides such as DDT and the cyclodienes may be in providing well-studied models to assess the advantages or disadvantages of new molecular biotechnologies as they become available for use in pesticide science.
The focus of my research effort is on the efficacious and environmentally sound use of pesticides. Specifically, my research team is interested in the molecular mechanisms of pesticide action on target and non-target organisms, xenobiotic metabolism of pesticides and molecular mechanisms of pesticide resistance. We examine the effects of pesticides in a variety of vertebrate and invertebrate systems and currently use molecular biological techniques to detect mutations.
Soderlund D.M., Clark J.M., Sheets L.P., Mullin L.S., Piccirillo V.J., Sargent D., Stevens J.T., and M.L. Weiner (2002) Mechanisms of pyrethroid neurotoxicity: implications for cumulative risk assessment. Toxicology 171:3-59
Putnam R.A., and J.M. Clark (2002) Persistence and Degradation of Chlorothalonil and Chlorpyrifos in a Cranberry Bog. J. Agric. & Food Sci. (in press).
Yoon K.S., and J.M. Clark (2002) Selective Induction of Abamectin Metabolism by Dexamthasone, 3-methylcholanthrene and Phenobartital in Colorado Potato Beetle, Leptinotarsa decemineata (Say). Pestic. Biochem. Physiol. 73: 74-86.
Haith D.A., Lee P.O., Clark J.M. Roy G.R. and M.J Imboden (2002) Modeling Pesticide Volatilization from Turf. J. Env. Qual. 31: 724-729.
Clark J.M., Lee S.H., Kim H.J. Yoon K.S. and A. Zhang (2001) DNA-based Genotyping Techniques for the Detection of Point Mutations associated with Insecticide Resistance in Colorado Potato Beetle. Pest Management Sci. 57: 1-7.
Lee, S.H., Yoon, K.S., Williamson, MS, Goodson, S.J., Takano-Lee, M., Edman, J.D., Devonshire, A.L. and Clark, J.M. (2000) Molecular Analysis of kdr-like Resistance in Permethrin-Resistant Strains of Head Lice, Pediculosis capitis. Pestic. Biochem. Physiol. 66:130-143.
Zhang, A., Dunn, J.B. and Clark, J.M. (1999) An Efficient Strategy for Validation of a Point Mutation associated with Acetylcholinesterase Sensitivity to Azinphosmethyl in Colorado Potato Beetle. Pestic. Biochem. Physiol. 64: 120-28.
Lee, S.H., Dunn, J.B., Clark, J.M. and Soderlund, D.M. (1999). Molecular Analysis of kdr-like Resistance in a Permethrin-Resistant Strain of Colorado Potato Beetle. Pestic. Biochem. Physiol. 63:63-75.
Tessier, D. M. and Clark, J. M. (1999) Hapten Design in the Development of Competitive Enzyme-Linked Immunosorbent Assays for Genotoxic Metabolites of Alachlor. J. Agric. Food Chem. 47: 3925-3933.
Clark, J.M. (1997) Insecticides as tools in probing vital receptors and enzymes in the nervous system. Review Article: In: Crop Protection Chemicals: Tools for Life Sciences (F. Matsumura, ed.) Pestic. Biochem. Physiol. 57, 225-254.
Beeman, R.W., Thomson, M.S., Clark, J.M., DeCamillis, M.A. and Denell, R.E. (1996) Woot, an active, gypsy-class retrotransposon in the flour beetle, Tribolium castaneum, is associated with a recent mutation. Genetics 143 (1), 417-426.
Zhu, K.Y. and Clark, J.M. (1996) A point mutation of acetylcholinesterase associated with azinphosmethyl resistance and reduced fitness in Colorado potato beetle. Pestic. Biochem. Physiol. 55, 100-108.
Zhu, K.Y. and Clark, J.M. (1995) Cloning and sequencing of a cDNA encoding acetylcholinesterase in Colorado potato beetle, Leptinotarsa decemlineata (Say). Insect Biochem. & Mol. Biology 25 (10), 1129-1138.
J. Marshall Clark (ed.), (1995) Molecular Action of Insecticides on Ion Channels. ACS Symposium Series 591, ACS Books, Washington, D.C., pp. 1-356.