Biography
Education
Ph. D. 1994 Biochemistry, University of Connecticut
MWPS 1983 Wood and Paper Science, with minor in Toxicology, North Carolina State University
BS 1980 Biochemistry, North Carolina State University
Research Interests
Larval settlement and metamorphosis
Invertebrate reproduction and development
Comparative physiology and biochemistry
Current research projects
Effects of serotonin on settlement and metamorphosis of the polychaete annelid Capitella teleta
In regulating settlement and metamorphosis of the marine polychaete annelid Capitella, we have previously found that nitric oxide acts as an inhibitory neuromodulator. We are now doing research investigating whether or not the release of serotonin as a stimulatory neurotransmitter is also involved in this regulation. Our results have so far shown that serotonin, and also fluoxetine which blocks reuptake of serotonin are able to induce settlement and metamorphosis, and that ketanserin which is an inhibitor of serotonin 5HT-2 receptors blocks this response. We are now trying to demonstrate the presence of 5HT-2 receptors in these larvae using immunofluorescence.
Influence of algae and bacteria on induction of settlement and metamorphosis of Capitella teleta larvae
We are now investigating whether or not certain species of algae and bacteria isolated from marine sediments can act as natural inducers of settlement for Capitella teleta, and also if the larvae are responding to a specific "chemical cue" in the sediments.
Investigation into the effect of 2,4-decadienal on growth and reproduction of Capitella teleta.
Marine diatoms are known to produce toxic aldehydes which adversely affect the reproduction and development of several marine invertebrates. We are now carrying out experiments to determine the effect of one of these aldehydes, 2,4-decadienal, on growth and reproduction of Capitella.
Assessment of Oxidative Stress in Passerine Birds
In collaboration with Dr. Jeff Stratford, we have begun to assess levels of oxidative stress in several species of passerine birds by measuring levels of the oxidative stress associated enzymes glutathione-s-transferase and glutathione peroxidase as part of a project which has received funding from the Pennsylvania Department of Conservation and Natural Resources (DCNR).
We are hoping to correlate levels of oxidative stress with exposure to environmental contaminants encountered in different habitats.
Courses taught
Invertebrate Biology
Comparative Physiology
Chemical Ecology
Human Anatomy and Physiology
Professional Preparation Techniques
Selected publications
Biggers, W.J., A. Pires, J.A. Pechenik, E. Johns, P. Patel, T. Polson, and J. Polson. 2012.
Inhibitors of Nitric Oxide Synthase Induce Larval Settlement and Metamorphosis of the
Polychaete Annelid Capitella teleta. Invertebrate Reproduction and Development 56:1-13.
Laufer, H., X. Pan, W.J. Biggers, C.P. Capulong, J.D. Stuart, N. Demir, and U. Koehn. 2005.
Lessons learned from inshore and deep-sea lobsters concerning alkylphenols. Invertebrate
Reproduction and Development 48: 109-117.
Laufer, H., N. Demir, and W.J. Biggers. 2005. The lobster's response to the effects of shell
disease. Journal of Shellfish Research 24: 757-760.
Biggers, W.J. and H. Laufer. 2004. Identification of juvenile hormone-active alkylphenols in the
lobster Homarus americanus and in marine sediments. Biological Bulletin 206: 13-24.
Laufer, H. and W.J. Biggers. 2001. Unifying Concepts Learned from Methyl Farnesoate for
Invertebrate Reproduction and Post-Embryonic Development. Amer. Zool. 41: 442-457.
Biggers, W.J. and H. Laufer. 1999. Settlement and metamorphosis of Capitella larvae induced
by juvenile hormone-active compounds is mediated by protein kinase C and ion channels.
Biological Bulletin 196: 187-198.
Biggers, W.J. and H. Laufer. 1996. Detection of juvenile hormone-active compounds by
larvae of the marine annelid Capitella sp. I. Arch. Insect Biochem.Phys.32: 475- 484.
Biggers, W.J. and H. Laufer. 1992. Chemical induction of settlement and metamorphosis of
Capitella capitata sp. I (Polychaeta) larvae by juvenile hormone-active compounds.
Invert. Reprod. Dev. 22: 39-46.
Laufer, H. and W.J. Biggers. 1992. Juvenile hormone-like compounds in Crustacea and their
implications for receptor evolution. In: Recent Advances in Cellular and Molecular
Biology, Vol. 4, R. Wegmann and M. Wegmann, Eds., Peeters Press, Leuven, Belgium,
pp. 301-311.
