Students need to think critically and write clearly about scientific concepts. Acquiring these skills as undergraduates prepares them well for whatever the next step might be.
Nervous-system development is a complicated process. For Professor Elizabeth Marin, biology, fruit flies provide an ideal means of exploring both the initial growth and the reorganization of neurons.
"Drosophila are excellent subjects because they go through such dramatic change," says Marin, whose expertise includes molecular biology, genetics and neuroscience. "At each stage of development, a different type of nerve cell is produced in a brain structure known as the mushroom body." She and her students manipulate ecdysone, a steroid hormone, to test its effects as fruit flies metamorphose from limbless larvae to flying adults. "We're studying how ecdysone controls reorganization of mushroom body neurons during metamorphosis, when the neurons prune their larval connections and make new connections to adult-specific targets."
Marin and her students also study the Hox genes, which control development along the anterior-posterior (head-tail) axis. In fruit flies, they determine whether legs, antennae or wings will develop as well as the survival and shape of the neurons that must control these structures. By manipulating selected genes, Marin's team creates neurons with mutant characteristics that help us understand the rules of normal development-and their findings can ultimately apply to humans as well as fruit flies.
Studying anything as miniscule as a fruit-fly brain demands state-of-the-art technology such as the confocal microscope Marin and her biology colleagues acquired through an NSF Major Research Instrumentation Grant. "My department is really well equipped," says Marin. "So people sometimes assume I have a fancy robotic system to perform the Drosophila dissections for us. I have to laugh. No, my students and I do them all by hand. It's a painstaking process, but it's really the only way to get it done."
Marin starts her students in the lab early to give them more hands-on experience with the equipment and the techniques — and to increase the likelihood that they will be able to help prepare a publication on their findings before they graduate. Her students not only present their projects at national meetings, but they also run a journal club on current papers in the field.
"I think it is very important for students to be reading and responding to primary literature," she says. "They need to think critically and write clearly about scientific concepts. Acquiring these skills as undergraduates prepares them well for whatever the next step might be."
Posted Sept. 30, 2015