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Listed below are short descriptions of the research projects of the faculty-led research groups in the Department of Biology, along with a list of selected publications related to these research interests.

Tennessee Coneflower, an endangered species

Kenton Brubaker Horticulture

My research is focused on the responses of plant cells to various stressful environmental situations. Plants, like animals, are continuously subject to a large number of environmental insults including drought, cold stress, salinity, disease, toxic pollution, insect herbivory and disease. While some plants have evolved to specifically combat one of these stresses, (as cacti have special abilities to withstand drought), all plants have adaptive ability to tolerate most stresses (to varying degrees). This is acheived by their activation of various enzymes and/or the transcription of certain genes. My research project focuses on the role of calcium ion fluctuations and hydrogen peroxide formation during plant cell responses to disease agents such as bacteria and fungi, and to other environmental cues such as hyper-osmotic stress (drought), wounding and cold shock. Students working on this project may have the opportunity to learn several different techniques including eukaryotic cell culture, luminometry, fluorimetry, DNA isolation, and the genetic transformation of bacteria and plants.

Northern Saw-whet Owls (NSWO) are known as breeding birds of the boreal forests in northern US and Canada. Although some observers observed migration in NSWOs many years ago, it has only been in the last 20 years that banding research has firmly established this phenomenon and clarified the pattern and dynamics of that migration. In the fall of 2001 I established a banding station at Highland Retreat Camp for the purpose of monitoring the migration of Northern Saw-whet Owls in western Virginia. The only other saw-whet banding station in Virginia at that time was on the eastern shore of Virginia. In 15 nights of banding that first year I caught and banded 122 owls, including six that were previously banded at other banding stations north of us. Since then I have continued the banding each fall (basically November) with similar but variable results. This station has become a part of a loose network of banding stations known as Project Owlnet. Our goals are to establish the route, timing, and variability in NSWO migration. We are also studying differential migration between genders and age groups along with other amenable research topics. There are several dozen NSWO migration banding stations and recapture and recovery of banded birds is adding quickly to our knowledge of its basic biology. Students are welcome to and participate in this research in various ways.

My major research focuses on factors that influence the development and function of male accessory sex glands-prostate and seminal vesicle. Currently we are investigating the influences of neonatal exposure of phytoestrogen on subsequent development and function of male and female reproductive systems, including prostate and seminal vesicle structure and function. A new project, beginning in 2000 that involves two undergraduate students, will investigate the heterogeneity of the mouse anterior prostate by separating, isolating, and characterizing the major cell populations in this organ. Characterization of prostatic cell populations will include various biochemical and morphological parameters. Participating students will learn techniques in cell separation, cell culturing, cytochemistry, and morphometry.

Mercury is an environmental pollutant of particular relevance to the Shenandoah Valley. Mercury levels in organisms that live in the Shenandoah River have increased over the past several decades as this heavy metal is released from a nearby soil site that was contaminated in the 1950's. Heavy metals in general are recognized as having serious effects on the function of cells. Mercury, for instance, is known to exert its toxicity during the development of the nervous system. My laboratory is starting a project to measure environmental levels of mercury, and to begin investigating their handling by, and effects on, the tissues of aquatic animals. The fate of mercury in aquatic animals is of interest both with respect to their own, unique physiological responses, and with respect to their use as model systems for health-related research. Thus, the goal of this project is to couple data on environmental levels of mercury with an understanding of what effects mercury has on cells, and what actions are taken by cells to counteract mercury's toxic effects. This project has two parts: 1) the use of atomic absorption to measure levels of mercury in clam tissues from the Shenandoah River, and 2) the use of fluorescence microscopy to investigate cellular responses to mercury. During the 2000-2001 academic year, my students and I worked to get the instrumentation and techniques working for these projects, in addition to collecting preliminary data. Funds from the Jeffress Foundation will allow us to further development the microscope system, to work during the summer of 2002, and to eventually present the results at a national meeting. These projects fall within my broader interests of environmental physiology-the study of how animals survive in their diverse environments, and how that physiology is altered by environmental contaminants.

Mast cells are most often regarded as the cells that cause the unpleasant symptoms of allergy. A better understanding of the pathways involved in the development and functioning of mast cells may prove helpful as scientists continue to try to find ways to relieve or prevent those symptoms. This project will examine the effects of two cell communication proteins (called "cytokines") in relation to mast cell development and function. The influences of interleukin-3 (IL-3), a known growth factor for mast cells, and interleukin-4 (IL-4), a protein which plays a number of important roles in the immune system, will be studied by looking at mast cells in mice which have been genetically engineered such that they lack these proteins. In collaboration with a research team at JMU, we will obtain mast cells from these "knockout" mice and compare their development and function with those of normal "wild type" mice. Students participating in this project will become familiar with gene-targeting techniques, and will gain experience in polymerase chain reaction (PCR), agarose gel electrophoresis, tissue culture, enzyme-linked immunosorbent assay (ELISA), and other cutting-edge research protocols.

 

Jim Yoder Small Mammal Trapping

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