Individual Listing

Entomology
University of California
Riverside, CA 92521

Beckage, Nancy E

Professor of Entomology, Cell Biology & Neuroscience

College of Natural and Agricultural Sciences

Entomology


Biography

Research Specialization - My laboratory has focused its efforts in deciphering the complexities of biochemical and molecular host-pathogen and hostparasite relationships, with special emphasis on wasp parasitoids that kill their hosts. The wasp parasitoid Cotesia congregata injects a polydnavirus (polydisperse DNA virus) into its host, the tobacco hormworm (Manduca sexta). The wasp genome contains integrated viral sequences, and the viruses replicate only in the female wasp's ovarian calyx tissue. The viruses cause host immunosuppression (the equivalent of an insect AIDS-like virus), allowing the parasitoids to mature without invoking a host immune response. The polydnavirus triggers apoptosis of host hemocytes, thus causing the host to be immunosuppressed during the initial stages of parasitic infection. Integration of viral sequences in the genomic DNA of the wasp itself is under study. Future studies are being directed at deciphering the role of virus-encoded proteins in causing host immunosuppression. Another area of special interest concerns the role of the parasitoid's polydnavirus in the successful interaction between the parasites and their host via expression of PDV gene products. A major hemolymph protein is induced to appear in the host beginning immediately following parasitization and this protein is a polydnavirus transcript. Host hemocytes, fat body, and other tissues participate in its synthesis to varying degrees. Viral DNAs persist in the host for the duration of parasitism. We are now exploring the biological role of the protein in causing host immunosuppression and other physiological changes. Endocrine relationships between the partners also are being examined, with particular emphasis on mechanisms of host developmental arrest involving endocrine and neuroendocrine disruption. Parasitized larvae show enhanced accumulation of neuropeptides in neurosecretory cells of the endocrine system. Hundreds of species of wasp parasitoids cause a similar host arrest, hence their utility as biological control agents. A common mechanism, such as disruption of neuropeptide release, may account for many species' ability to cause developmental arrest of their host insect in a pre-metamorphic state. The hemolymph ecdysteroid titer of the host peaks shortly before the wasps emerge. Wasp endo- and ectoparasitoids clearly have evolved the capacity to interact with their host via a variety of complex hormonal and biochemical interactions. This is particularly true of parsitoids that ultimately induce developmental arrest and cause death of the host. Behavioral effects of parasitism are also seen.

Former Institution

 University of Wisconsin-Madison

Degrees

BS Zoology 1972

University of Wisconsin

PhD Zoology 1980

University of Washington

Awards

2009 Who's Who in America
2008 Honorary Ph.D. from ETH Zurich, Switzerland, for research contributions to the fields of insect endocrinology and immunology
2005 Chancellor's Faculty Award for Excellence in Mentorship of Undergraduate Research
2003 American Association for the Advancement of Science, Biological Sciences
1996 UC Riverside "Women Who Make a Difference Award"
1996 Miller Visiting Research Professor, University of California Berkeley
1992 Distinguished Lectureship, Montana State University - Molecular Biology January
1975-79 National Institutes of Health Developmental Biology Predoctoral Fellowship


Research Area

Physiological and molecular host-parasite, host-pathogen, host-parasitoid relationships. Insect immunity, pathology, virology, endocrinology, and behavior. Parasitoid polydnaviruses and their roles during parasitism. Mosquito vector biology, physiology, and vector-parasite interactions.

I: Parasitoid-Host Interactions

Host-Parasitoid Interactions Parasites and pathogens induce dramatic alterations in the physiology and behavior of insect hosts. Our laboratory uses two lepidopteran host:wasp parasitoid systems to study physiological, biochemical, and molecular host-parasite interactions: the tobacco hornworm, Manduca sexta, and the braconid parasitoid Cotesia congregata; and the sugarcane borer, Diatraea saccharalis, and Cotesia flavipes as model systems. Manduca sexta is refractory to Cotesia flavipes and the parasitoid’s eggs are encapsulated by host blood cells, and this interaction is being explored as an immunity model. The roles of the parasitoid’s polydnavirus in suppressing host growth, development, and immunity in susceptible hosts are under study. Parasitoid polydnavirus genes that can be exploited in development of recombinant biopesticides with enhanced virulence for lepidopteran larvae and are also under study. Endocrine host-parasite interactions involving juvenile hormone and ecdysteroid coordinate the development of parasite and host, and we are studying the endocrine mechanisms responsible for induction of host developmental arrest with the goal of using this information in formulation of biopesticides to kill target insect pests. In addition, neural regulation of the host’s behavior during parasitism and the mechanisms responsible for cessation of host food consumption prior to emergence of the wasps from the host are being analyzed. The induction of host anorexia is adaptive for the emerging wasps, which otherwise would be consumed by a feeding host during parasitoid egression from the host. The Manduca sexta-Cotesia congregata system is being utilized as our model because of the wealth of available information that describes Manduca neurobiology and behavior.

II: Biology of Mosquitoes and Biologically-based Control Strategies

Our laboratory is developing biologically-based control strategies to control mosquito populations and reduce transmission of vector-borne diseases both in California (West Nile Virus) and globally. Ecdysone agonists are a new class of biopesticide that induces precocious lethal molting in larval stage mosquitoes (Beckage et al., 2004). Our research on these insect growth regulators will facilitate development of new biopesticides to control vectors of West Nile virus, malaria, and other pathogens and parasites. Our laboratory has studied effects of ecdysone agonists on the mosquito species, Anopheles gambiae, Aedes aegypti, and Culex quinquefasciatus, all of which vector disease on a global scale. Biological control of mosquitoes using pathogens (fungi) is also being studied in the Beckage laboratory.

III. International Research and Training Projects

Recent grant funding awarded to our laboratory will facilitate participation of both undergraduate and graduate students in research and training projects in Mali, West Africa. Malaria transmission is the single most important factor affecting human health and agricultural productivity in Africa. Our goal is to conduct translational research and develop new paradigms for controlling mosquito-borne disease transmission and crop pests. The interface between agriculture and human health is being emphasized in this research. Faculty and students from University of California-Riverside, Montana State University, University of California-Davis, Virginia Tech, University of St. Thomas, and Chief Dull Knife College are partners in this collaborative effort. More information about the Mali-based undergraduate and graduate student training project can be found at: http://www.insideucr.ucr.edu/cgi-bin/display.cgi?id=765

Publications

Edited Books

Beckage, N.E. 2008. “Insect Immunology” Academic Press/Elsevier.

Beckage, N.E. 1997. "Parasites and Pathogens: Effects on Host Hormones and Behavior" Chapman and Hall.

Beckage, N.E., Thompson, S.N., and Federici, B.A. 1993. "Parasites and Pathogens of Insects", Vol. 1: Parasites, Vol. 2: Pathogens. Academic Press.

Edited Journal Special Issues

Beckage, N.E. and Stanley, D.W. 2008. Guest editor, special issue of Archives of Insect Biochemistry and Physiology “Parasitoid Polydnaviruses: Genomes and Physiological Functions" 67:155-209.

Beckage, N.E. 2008. Guest editor, special issue of Archives of Insect Biochemistry and Physiology on “Parasitoid Polydnaviruses: Genomes and Physiological Functions.” In press.

Palli, S.R., Webb, B.A. and Beckage, N.E. 2007. Guest editor, special issue of Insect Biochemistry and Molecular Biology “In Honour of Lynn M. Riddiford” Vol. 37: 739-890.

Beckage, N.E. and Reynolds, S.E. 2007. Guest editor, special issue of Journal of Insect Physiology focusing on “Physiology of Vector Arthropods” Vol. 53: 205-284.

Beckage, N.E. 2005. Guest editor, special issue of Archives of Insect Biochemistry and Physiology on “Physiological and Behavioral Host-Parasitoid Interactions: Future Visions.” Vol. 60: 151-235.

Beckage, N.E. 2003. Guest editor, special issue of Journal of Insect Physiology on "Insect Polydnaviruses: Evolution and Physiological Functions." Vol. 49:395-543.

Articles for General Interest Audiences

Beckage, N.E. 1997. Parasitoids and polydnaviruses. BioScience 48: 305-311.

Beckage, N.E. 1997. The parasitic wasp's secret weapon. Scientific American 77: 32-37.

Selected Publications

Beckage, N.E. 2009. Immunology. In: "Encyclopedia of Insects" (edited by V. Resh and R. Carde) Academic Press/Elsevier. In Press.

Butler, C.D., Beckage, N., Trumble, J.T. 2009. Effects of terrestrial pollutants on insect parasitoids. Environmental Toxicology and Chemistry 28: 1111–1119.

Gordillo, A.R. and Beckage, N.E. 2008. Fungi as biological controls of insect disease vectors. Microbiology Today 35: 104.

Rodriguez-Perez, M.A. and Beckage, N.E. 2008. Comparison of three methods of parasitoid genomic DNA isolation to facilitate polydnavirus genomic sequencing. Archives of Insect Biochemistry and Physiology 67: 202-209.

Beckage, N.E. 2008. Parasitoid polydnaviruses and insect immunity. In: “Insect Immunology” (edited by N.E. Beckage) pp. 243-270. Academic Press/Elsevier.

Schmidt, O., Theopold, U., and Beckage, N.E. 2008. Insect and vertebrate immunity: Key similarities vs. differences. In: “Insect Immunology” (edited by N.E. Beckage) pp. 1-23. Academic Press/Elsevier.

Dorn, S., and Beckage, N.E. 2007. Superparasitism in gregarious hymenopteran parasitoids: ecological, behavioural and physiological perspectives. Physiological Entomology 32: 199-211.

Rodriguez-Perez, M.A., and Beckage, N.E. 2006. Co-evolucion de parasitoids y polydnavirus [Co-evolution of parasitoids and polydnaviruses] Revista Latinoamerica de Microbiologia 48: 31-43 [In Spanish with English abstract].

Webb B.A., N.E. Beckage, Y. Hayakawa, P.J. Krell, B. Lanzrein, M.R. Strand, D.B. Stoltz, M.D. Summers. 2005. Polydnaviridae. In: “Virus Taxonomy: VIII Report of the International Committee on Taxonomy of Viruses” (C.M. Fauquet, M.A. Mayo, J. Maniloff, U. Desselberger, L.A. Ball, eds.) Elsevier, pp. 253-259.

Rodriguez, M.A., Dumpit, R., Lenz, J., Powell, E., Tam, S., and Beckage, N.E. 2005. Host refractoriness of the tobacco hornworm, Manduca sexta, to the braconid endoparasitoid Cotesia flavipes. Arch. Insect Biochem. Physiol. 60: 159-171.

Amaya, K.E., Asgari, S., Jung, R., Hongskula, M., and Beckage, N.E. 2005. Parasitization of Manduca sexta larvae by the parasitoid wasp Cotesia congregata induces an impaired host immune response. J. Insect Physiol. 51:505-512.

Beckage, N.E., Marion, F.M., and Tan, F.F. 2004. Comparative larvicidal toxicities of three ecdysone agonists on the mosquitoes Aedes aegypti, Culex quinquefasciatis, and Anopheles gambiae. Arch. Insect Biochem. Physiol. 57:111-122.

Beckage, N.E. and Gelman, D.B. 2004. Wasp parasitoid disruption of host development: Implications for new biologically based strategies for insect control. Ann. Rev. Entomol. 49: 299-330.

Le, N.T., Asgari, S., Amaya, K., Tan, F.F. and Beckage, N.E. 2003. Persistence and expression of Cotesia congregata polydnavirus in host larvae of the tobacco hornworm, Manduca sexta. J. Insect Physiol. 49: 533-543.

Beckage, N.E., Hongskula, M., Vickerman, D. and Tan, F.F. 2003. Development of the solitary braconid endoparasitoid Cotesia marginiventris in the sphingid host, Manduca sexta. J. Invert. Pathol. 83: 253-256.

Beckage, N.E. 2003. Immunology. In: "Encyclopedia of Insects." (V. Resh and R. Carde). Pp. 555-560, Academic Press.

Beckage. N.E. and Tan, F.F. 2002. Development of the braconid wasp Cotesia congregata in a non-habitual noctuid host, Trichoplusia ni. J. Invert. Pathol. 81: 49-52.

Beckage, N.E. 2002. Parasite- and pathogen-mediated manipulation of host hormones and behavior. In: "Hormones, Brain, and Behavior" Vol. 3 (D. Pfaff, A. Arnold, A. Etgen, S. Fahrbach, and R. Rubin eds.) pp. 281-315. Academic Press.

Belle, E., Beckage, N.E., Rousselet, J., Poirie, M., Lemeunier, F. and Drezen, J.M. 2002. Visualization of polydnavirus sequences in a parasitoid wasp chromosome. J. Virol. 76: 5793-5796.

Beckage, N.E., Foreman, R.C., Palmatier, C.M., and Tan, F.F. 2002. Inhibition of the larval ecdysis and emergence behavior of the parasitoid of the parasitoid Cotesia congregata by juvenile hormone. J. Insect Physiol. 48: 725-732.

Cole, T.J., Beckage, N.E., Tan, F.F., Srinivasan, A., and Ramaswamy, S.B. 2002. Parasitoid-host endocrine relations: self-reliance or co-optation? Insect Biochem. Molec. Biol. 32: 1673-1679.

Beckage, N.E. and Gelman, D.B. 2001. Parasitism of Manduca sexta by Cotesia congregata: A multitude of disruptive endocrine effects. In "Endocrine Interactions of Insect Parasites and Pathogens" (J. Edwards. and R. Weaver, eds.) pp. 59-81. BIOS Scientific Publishers, Oxford.

Washburn, J.O., Haas-Stapelton, E.J., Tan, F.F., Beckage, N.E. and Volkman, L.E. 2000. Co-infection of Manduca sexta larvae with polydnavirus of Cotesia congregata increases susceptiblity to fatal infection by Autographa californica M nucleopolyhedrovirus. J. Insect Physiol. 46: 179-190.