Johns Hopkins researchers A. R. Tomas and M. R. Deans have identified a protein needed for neuron organization in the developing retina. The team says that the study helps reveal how the healthy retina – the part of the eye that detects light – is built, and will lead to a greater understanding of what goes wrong in eye disease.
In order for the eye to see, light-detecting cells must transmit information to neurons in the retina that relay the signal to the brain. One type of eye neuron, amacrine cells, pools information from the other eye neurons and directs output neurons, called retinal ganglion cells, to transmit the visual information to the brain. Normally the amacrine and retinal ganglion cells are found in distinct layers of the retina. However, when the researchers engineered mice to lack the protein Fat3 in their retinal ganglion cells, the researchers found that the amacrine cells moved into the space usually reserved for the retinal ganglion cells. The researchers also observed that the amacrine cells in these modified mice contained extra projections used to detect information from neighboring retina cells. These extra projections extended into parts of the retina where they usually aren’t found.
“Studies in fruit flies show that Fat3 is important for tissue growth, but surprisingly, in the mouse retina, Fat3 has nothing to do with growth and everything to do with neuron organization and development,” says Michael Deans, Ph.D., assistant professor of neuroscience and otolaryngology. Deans says they haven’t determined whether loss of Fat3 in the eye’s neurons affects vision yet, but the group plans to continue studies on Fat3′s other roles in the eye.
Johns Hopkins researchers at American Society of Cell Biology Annual Meeting
Special Interest Subgroup: Tissue Development and Morphogenesis II