Bringing a Fresh Eye to Research
 Beth Ann Cimini: Visual Coordination
Singing with an a cappella group, with its harmonies and multiple voices meshing into one song, parallels in some ways the coordination of the body’s nervous system, where multiple stimuli must be integrated into a singular experience. Perhaps, then, it’s no surprise that one of Boston University’s most gifted young neurobiology students is also an a cappella singer.
Junior Beth Ann Cimini, the first in her family to study science, is the recipient of a coveted two-year Beckmann Grant for undergraduate research. She has taken up the challenge of understanding how the retina processes visual stimuli. Specifically, she is looking at the role of the neurotransmitter acetylcholine, a chemical relay that operates in the synapses, or junctions, between nerve cells.
While the eye may seem a marvelous piece of stand-alone biological architecture, Cimini says much of it is derived from the same tissue as the nervous system. This means that parts of the eye that connect directly to the brain—the retina and the optic nerve—use similar means to produce the visual messages generated there.
Under the guidance of her advisor, neurobiology professor Bill Eldred, and in partnership with researchers at the University of Alabama, Cimini is studying how acetylcholine activates nitric oxide, another key neurotransmitter in the retina. In muscle cells, for example, acetylcholine is released into the synapse and triggers the opening of ion channels that cause muscle contraction. In the retina, however, it appears that acetylcholine not only acts directly to generate nerve impulses but also works indirectly through a series of other chemicals.
Using a special staining technique called immunocytochemistry, in which a fluorescent protein is attached to a particular target cell, Cimini is looking at how acetylcholine initiates a “chain” or “cascade” of chemicals that generate nerve impulses in the retina. Her work suggests that acetylcholine may “turn on” nitric oxide, which, in turn, activates another set of chemicals known as cyclic GMPs, or cGMPs. “The cGMPs appear to determine which cells are being turned on and off,” she says.
Cimini’s work contributes to a clearer view of how the eye itself may process visual information before it is sent to the brain. “The more complex the system, the more complete a picture that can be generated in the eye itself, before the brain even becomes involved.”
—by Jeremy Miller |
