Something in the Way it Moves

Dr. James Newcomb Studies Locomotion in Sea Slugs

For Dr. James Newcomb, Assistant Professor of Biology, the simpler the better when it comes to studying the nervous systems of invertebrates. The sea slug Melibe leonina has proven to be the perfect subject for his ongoing research. This shell-less mollusk has a very special talent that most of the other 3,000 species of nudibranch don’t – it swims. And by studying Melibe leonina, Dr. Newcomb wants to know how the nervous system produces certain behaviors, and the parallel question, how the nervous system evolves to produce different behaviors. As Dr. Newcomb puts it, “Getting to the answers is a lot easier with invertebrates.”

Much of Dr. Newcomb’s previous work has centered around the effects of serotonin on the sea slug’s neurons and its locomotion. “We have identified the neurons that produce swimming behaviors. The question is whether serotonin is working at the circuit level.”

Studying the sea slug offers scientists an opportunity to observe the evolution of the species’ nervous system as well. “Certain sea slugs locomote in different ways,” notes Dr. Newcomb. “By studying the varieties of movement, we expect to see how the nervous system changes and evolves to allow for new behaviors. The same neurons in different species don’t necessarily perform the same behaviors.”

Through the funds provided by the recent INBRE grant, Dr. Newcomb and his students will turn their attention to the sea slug’s circadian rhythms. “We are looking at where the circadian clock is located in the brain of Melibe and how this clock communicates with other parts of the brain, such as the circuits controlling locomotion. As Dr. Newcomb explains, scientists already know how sea slugs move and how the brain controls this form of locomotion. “But where the clock that drives the sea slug’s circadian rhythm is located and how that clock controls the organism at the neural level has not been asked yet. That’s where we see this research taking us.”

“NEC is a great place to conduct research,” observes Dr. Newcomb. “We’re not a large research institution so it is more practical to collaborate with other institutions.” With the award of the INBRE grant, research at NEC will improve dramatically. Not only will the College’s laboratory facilities undergo a transformation, but Dr. Newcomb sees great opportunities for collaboration with institutions like Dartmouth College and the University of New Hampshire. “The focus of this grant is on the student,” notes Dr. Newcomb. “INBRE provides opportunities for students on a whole new scale including funds for equipment, stipends for student employment, and opportunities for professional development.”

For more information about the New Hampshire Network of Biomedical Research Excellence (NH-INBRE), please visit their website at http://nhinbre.org.