David W. Borst, Ph.D.
Professor of Biology
Department of Biology
University of Central Florida
4000 Central Florida Blvd
Orlando, FL 32816-2368
Phone: (407) 823-1460 Fax (407) 823-0715
Email: dborst@mail.ucf.edu
My research is focused on comparative endocrinology, with specific interests in arthropod development, growth, and reproduction. We study these topics using biochemical, cellular and molecular biology techniques. Some of the projects in my laboratory are outlined below:
Background: Hormones have important roles in the regulation of many physiological, developmental, and behavioral processes. Perhaps nowhere is this regulation more critical than during molting and reproduction. Molting is critical for the continued growth and survival of the individual. Similarly, the production of offspring is critical for the survival of the species. Both processes must be adjusted to meet rapid changes in the environment. My lab is studying the physiological and cellular mechanisms used by arthropods to regulate their molting and reproduction. We are particularly interested in the role(s) of the juvenile hormones (JH) and methyl farnesoate (MF) (see Figure 1) in regulating these processes in grasshoppers and lobsters, respectively. To this end, we have developed sensitive methods (RIA, HPLC, ELISA) to measure hemolymph levels of several compounds, including JH, MF, and vitellogenin (Vg, the yolk protein precursor).
Projects with crustaceans: In one project (supported by the NSF) we are isolating neuroendocrine peptides that regulate MF production in lobsters and other crustaceans. These peptides will then be used to modify endogenous levels of MF in these animals. In addition, we have characterized and cloned some of the enzymes involved in the production of MF, including farnesoic acid O-methyl transferase and HMG-CoA reductase to better understand how this compound is produced. Finally, we have recently obtained a partial clone for vitellogenin (the precursor of yolk protein) and are using it to investigate the regulation of reproduction.
Projects in insects: In a second NSF-supported project, we are studying how nutrition affects grasshopper molting and reproduction. We have measured the levels of JH, ecdysteroids, Vg, and storage proteinss in the hemolymph during molting and reproduction. In addition, we have partially cloned the cDNAs for both vitellogenin and the storage proteins. We are using this information to investigate how the synthesis of these two proteins is regulated by JH and by other compounds.
Recent Publications
Li, S. Ouyang, Y. C., Ostrowski, E., and Borst, D. W. 2005. Regulation of juvenile hormone synthesis by the corpora allata from the lubber grasshopper, Romalea microptera. Peptides. 26: 63–72. PDF
Mutun, S. and Borst, D. W. 2004. Intraspecific mitochondrial DNA variation and historical biogeography of the lubber grasshopper, Romalea microptera. Annals of the Entomol. Soc. of America 97: 681-696. PDF
Li, S., Friesen, J. A., Fei, H., Ding, X., and Borst, D. W. 2004. The lobster mandibular organ produces soluble and membrane-bound forms of 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Biochem J. 381:831-40. PDF
Holford, K. C., Edwards, K. A., Bendena, W. G., Tobe, S. S, Wang, W., and Borst, D. W. 2004. Purification and characterization of a mandibular organ protein from the American lobster, Homarus americanus: a putative farnesoic acid O-methy-transferase. Insect Biochem. Mol. Biol. 34:785-98. PDF
Hatle, J. D., Miller, W. A., and Borst, D. W. 2003. Canalization of development and ecdysteroid timing during the last instar in lubber grasshoppers. J. Insect Physiol. 49: 73-80 PDF
Borst, D W., G. Wainwright, and H. H. Rees. 2002. In vivo regulation of the mandibular organ in the edible crab, Cancer pagurus. Proc.Royal Soc.: Biol. Sci. 269: 483-490. PDF
Lovett, D.L., Verzi, M.P., Clifford, P.D. and Borst, D.W. 2001. Hemolymph levels of methyl farnesoate increase in response to osmotic stress in the green crab, Carcinus maenas. Comp. Biochem. Physiol. A:128:299-306.
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