Dr. James Ferrari
B.A., Queens College, City University of New York
M.S., University of California Riverside
Ph.D., University of California Riverside
Insecticide resistance is a serious obstacle to the effective control of insect vectors of disease. While resistance has long been recognized as an evolutionary phenomenon, we know relatively little about the genetic and population processes which influence the dynamics of genes for resistance in populations.
In the mosquito Culex quinquefasciatus, resistance to organophosphate insecticides is associated with a highly active esterase allozyme, designated EST-B1. The molecular basis of high esterase activity in resistant individuals is high esterase enzyme titer, due to amplification (increase in copy number) of the EST-B1 gene. Individuals from a highly resistant strain can carry 250 times the number of EST-B1 gene copies, and exhibit 120 times the esterase activity of susceptible individuals.
The overall objective of my current research is to understand the genetic processes and evolutionary forces influencing the dynamics of amplified EST-B1 genes in populations. Under funding from the National Institutes of Health we are investigating how genetic processes interact with insecticidal selection to produce individuals with high esterase activity, the stability properties of these high activity phenotypes, and how esterase activity phenotype affects reproductive fitness in the presence and absence of insecticide. The long-term goal of my work is to provide the information necessary to design vector control strategies which minimize the rate of evolution of resistance.
Ferrari, J. A. 2015. Genetic characterization of esterase activity variants associated with an esterase gene amplification in a strain of Culex pipiens from California. J. Am. Mosq. Contr Assoc. 31: 7-15
Wirth, M. C., J. A. Ferrari, and G. P. Georghiou 2001. Baseline susceptibility to bacterial insecticides in populations of Culex pipiens complex (Diptera:Culicidae) from California and from the Mediterranean Island of Cyprus. J. Econ. Entomol. 94: 920-928
Ferrari, J. A. 2001. Response of a low level gene amplification to organophosphate selection in Culex pipiens. Resistant Pest Management 11:37.
Ferrari, J. A. 1996. Chapter 30: Insecticide Resistance. In: Biology of Disease Vectors. B.J. Beaty and W.C. Marquardt (eds.), University of Colorado Press.
Ferrari, J. A., J. G. Morse, G. P. Georghiou, and Y. Sun. 1993. Elevated esterase activity and acetylcholinesterase insensitivity in citrus thirps (Thysanoptera: Thripidae) populations from the San Joaquin Valley of California. J. Econ. Entomol. 86: 1645-1650.
Ferrari, J. A. and G. P. Georghiou. 1991. Quantitative genetic variation of esterase activity associated with a gene amplification in Culex quinquefasciatus. Heredity 66: 265-272.
Ferrari, J. A. and G. P. Georghiou. 1990. Esterase activity variation within and among insecticide resistant, susceptible, and heterozygous strains of Culex quinquefasciatus. J. Econ. Entomol. 83: 1704-1710.
Ferrari, J. A. and K. S. Rai. 1989. Phenotypic correlates of C-value differences among strains of Aedes albopictus. Evolution 43: 895-899.
Ferrari, J. A. and G. P. Georghiou. 1988. Preliminary genetic studies of esterase activity variation associated with organophosphate resistance in Culex quinquefasciatus. Proc. Calif. Mosq. and Vector Control Assoc. 56: 204-207.
Black, W. C., IV, J. A. Ferrari, K. S. Rai and D. Sprenger. 1988. Breeding structure of a colonizing species: Aedes albopictus in the United States. Heredity 60: 173-181.
Ferrari, J. A. 1987. Components of genetic variation associated with second and third chromosome gene arrangements in Drosophila melanogaster. Genetics 116: 87-97.
Taylor, C. E., A. Pereda and J. A. Ferrari. 1987. On the correlation of mating success and offspring quality in Drosophila melanogaster. Am. Nat. 129: 721-729.
Ferrari, J. A. and G. P. Georghiou. 1981. Effects of insecticidal selection and treatment on the reproductive potential of resistant, susceptible, and heterozygous strains of the southern house mosquito. J. Econ. Entomol. 74: 323-327.
Ferrari, J. A. and C. E. Taylor. 1981. Hierarchical patterns of chromosome variation in Drosophila subobscura. Evolution 35: 391-394.
BIOL 321 - Evolution
BIOL 202 - Biology of Populations
BIOL 421/422 - Genetics & Genetics Lab