Until now, SyndicateMizzou has been highlighting the research and creative activities of MU faculty and staff. This current feature represents the first step in a new endeavor—to offer a survey of some of the exciting work being done by MU graduate students. Beginning with the Life Sciences, we have interviewed a handful of exceptional students, asking questions about what forces drew them to their specific area of research, the differences between undergraduate and graduate school, and why this research is significant. Whether they seek to find treatments for breast cancer and muscular dystrophy or better understand the science behind microscopic roundworms, soybean pathogens, oilseed production, or the ecology of forest-dwelling songbirds, watching these students talk about their work in their own words is nothing short of inspiring.
Brian Bostick, Molecular Microbiology and Immunology
Brian Bostick received a B.S. in Biochemistry from MU in 2002. As a graduate student in both MU’s School of Medicine and the Graduate School, he is working towards a career as a physician-scientist: “I hope to bridge the gap between research and medicine by translating my basic science research directly into clinical therapies for cardiovascular disease.” Bostick currently works in Dongsheng Duan's laboratory developing a cure for Duchenne muscular dystrophy (DMD). Children suffering from DMD are born with a mutation in a gene called dystrophin, a gene that makes an important protein to protect muscle cells from damage during stretching or contraction. Without dystrophin, DMD sufferers are wheelchair-bound before they are teenagers and die in their mid-twenties. While a great deal of research focuses on curing DMD, most of it has looked at treating skeletal muscle, ignoring one of the most important muscles of the body, the heart. Heart disease is a leading killer of DMD patients and occurs, to some extent, in every patient. Bostick hopes his research will help to enhance the understanding and treatment of DMD heart disease using viral gene therapy—an innovative procedure that puts therapeutic genes inside a virus and delivers them to the body. While they are often personified as terrible, disease-causing entities, viruses are actually very simplistic organisms. Their sole objective is to get inside the body’s cells in order to hijack the cell’s machinery and make more viruses. In viral gene therapy, this scenario is exploited to treat diseases. Bostick explains: “By replacing the virus’s genes with a dystrophin gene, we make the virus deliver our replacement gene to the cells. Then, instead of using the cells to make more viruses, the cells make the missing dystrophin and cure the disease.”
Andrew Cox, Division of Biological Sciences
Andrew Cox is a graduate student in the Division of Biological Sciences. After receiving a B.A. in English from the University of Florida in 1997, he worked in the corporate sector for several years before returning to school. Spending a year in post-baccalaureate studies, where he gained both lab and field experience with birds, he and his wife took field jobs in Arizona, Hawaii, and Venezuela before Cox applied to work with John Faaborg’s laboratory at MU. Cox’s current research focuses on how people’s land use affects the lives of birds. Even in the best conditions, forest-dwelling songbirds, for example Northern Cardinals, lose many of their eggs and young to such predators as snakes, owls, and blue jays. When historically forested landscapes become increasingly urban and/or agricultural, birds tend to lose many more eggs and young to nest predators. While this pattern has been observed numerous times in Eastern and Midwestern landscapes, the mechanism responsible for it remains unclear. Therefore, Cox is employing video cameras to determine which species are the dominant nest predators for forest songbirds in a Midwestern landscape, whether the dominant predators in heavily forested areas remain important as the landscape becomes increasingly fragmented, and whether factors that influence nest predation rates also influence which predators are the most important contributors to overall predation rates.
Erica Racen, Molecular Microbiology and Immunology
Erica Racen’s research is in the area of developmental genetics. Using microscopic earthworms, known as Caenorhabditis elegans, Racen studies germline development. The germline is made up of a distinct set of cells that have the ability to become the next generation, both eggs and sperm. It is important for scientists to understand the basics of how these cells develop in order to improve their knowledge regarding fertility and stem cell maintenance. In the laboratory of Karen Bennett, Racen is studying four proteins, termed the Germline RNA Helicases (GLH), which are found in germ cells throughout all stages of development. They have discovered that the GLHs are important for fertility and, in fact, when GLH-1 alone is missing the worm is sterile when placed at higher temperatures. Racen seeks to determine the role of GLH-1 in fertility and already has some very exciting data. It appears that GLH-1 has both a genetic and physical relationship to a protein known as Dicer, an essential protein in the RNA interference pathway, which controls protein production at the RNA level. They hypothesize that GLH-1 and Dicer work together in the germline, regulating the production of a specific set of proteins to ensure that germ cells develop properly and maintain their germ cell-like character. More research into the relationship will help reveal how the RNA interference pathway and the GLH proteins partner to maintain the integrity of the germline.
Amy Replogle, Division of Plant Sciences
Amy Replogle grew up in the state of Washington and has always had a love for the sciences. In high school she discovered an interest in biology and pursued a B.S. in Biology at the University of Puget Sound in Tacoma, Washington. While there Replogle became specifically interested in plant biology and pursued internships at Ohio State University and at MU, both positions involved in researching plant-pathogen interactions, a field that offers the benefit of studying a plant system and a pathogen system at the same time. After graduating from the University of Puget Sound in 2005, Replogle returned to the University of Missouri-Columbia, joining Melissa Goellner Mitchum’s Plant Nematology Lab in the Bond Life Sciences Center to study plant-nematode interactions. As a doctoral student, Replogle’s research has focused on two different soybean cyst nematode CLAVATA/ESR(CLE)-like genes that are secreted into the roots of soybean plants to induce the formation of cells in the root that allow the nematode to feed. Interestingly, these CLE-like genes are the only members of the CLE family found outside of the plant kingdom. In plants, this gene family has been shown to play a role in the maintenance of both shoot and root apical meristems by restricting the division of stem cells and promoting differentiation into shoot and root tissue. It is thought that nematode-secreted CLE peptides may mimic the plant CLE peptides to developmentally reprogram the fate of selected plant cells for feeding cell development. Knowing how feeding cells develop will be an important step toward understanding the basic biology of parasitism, so that such biotechnology approaches as engineered resistance can be made available to farmers.
Severin Stevenson, Department of Biochemistry
Severin Stevenson is currently a graduate student in Biochemistry. Both his background and current research are in plant biochemistry. He earned a masters degree in Biotechnology, with an emphasis in plant biochemistry, from the University of Nevada-Reno, in 2006. Working with David Shintani’s laboratory, Stevenson worked on two projects. One sought to understand the biosynthesis of latex (rubber) in plants; the other focused on the biosynthesis of thiamin (vitamin B1) in plants. His work in the rubber project involved creating a sustainable hairy-root culture using a model rubber producer called the Russian Dandelion. The roots produce the most latex, so that if a stable root culture could be produced, with the help of molecular genetics, these studies could be expedited. For the thiamin project, Stevenson studied the localization of ThiC protein in Arabidopsis thaliana using GFP tagging. Now at MU, Stevenson has been working with Jay J. Thelen’s Proteomics of Oilseeds Lab in the Bond Life Sciences Center, researching the regulation of fatty acid biosynthesis using plant suspension cell cultures. The regulatory mechanism governing the synthesis of fatty acids in plants is complex, and much of it remains undefined. In order to manipulate the production of oil in oilseed plants, one must understand how the plant self-regulates the process. Stevenson hopes to shed light on this regulatory mechanism using plant cell cultures, which allow him to apply sources of water-soluble fatty acids directly to the cells and study how they respond to an overabundance of fatty acids. Using mass spectrometry, Stevenson plans to define the regulatory points in this system in cultured cells and apply this knowledge to whole plants.
William Donald Thomas, Division of Biological Sciences
Born on the south-side of Chicago, Illinois, William Donald Thomas attended Saint Xavier University for two years and then Chicago State University where he earned a B.S. in biology in 1999, followed by an M.S. in chemistry at Arizona State University in 2002. After teaching as an instructor in the Biology Department at Claflin University in Orangeburg, South Carolina, in 2004 Thomas received a Life Science Fellowship and entered the biology graduate program at MU, where he is currently a PhD candidate working with George P. Smith’s Phage Display Lab. Responding to the fact that between 25-50% of metastatic ductal breast cancers are linked with the over-expression of an epithelial growth factor receptor (EGFR) called ErbB2, Thomas' research involves the use of affinity selection of specially constructed bacteriophage display libraries, to discover peptides with high affinity to the ErbB2 extra-cellular domain (ECD) and full length ErbB2 on breast cancer cell lines. Thomas is using ELISAs and Surface plasmon resonance (SPR) spectroscopy to characterize the binding interactions between ECD and the selected peptide ligands. The goal of this research is to create a panel of high affinity ErbB2 ligands that can be further developed into carriers of imaging or pharmaceutical agents to target breast cancers.