Critical retinal development gene identified

Baltimore-Researchers at Johns Hopkins Medicine have announced they have identified a gene that guides the separation of two types of motion-sensing cells, offering insight into how cellular layering develops in the retina, with possible implications for the brain’s cerebral cortex.

“The separation of different types of cells into layers is critical to their ability to form the precise sets of connections with each other-the circuitry-that lets us process visual information,” said Alex Kolodkin, PhD, a professor in the Johns Hopkins University School of Medicine’s Solomon H. Snyder Department of Neuroscience, and an investigator at the Howard Hughes Medical Institute. “There is still so much to learn about how that separation happens during development, but we’ve identified for the first time, proteins that enable two very similar types of cells to segregate into their own distinct neuronal layers.”

A report on the discovery is published in the Nov. 1 issue of the journal, Science.

Dr. Kolodkin’s research group specializes in studying how circuitry forms among neurons (brain and nerve cells). Past experiments revealed that two types of proteins, called semaphorins and plexins, help guide this process.

The current study focused on the genes that carry the blueprint for these proteins in 2 of the 10 layers of cells in the mammalian retina.

“We hope that learning how layering occurs in these very specific cell types will help us begin sorting out how connections are made, not just in the retina, but also in neurons throughout the nervous system,” Dr. Kolodkin said.

The National Institute of Neurological Disorders and Stroke, the National Eye Institute, the Human Frontier Science Program, the Weizmann Institute’s National Postdoctoral Award Program for Advancing Women in Science, and the Edmond and Lily Safra fellowship for postdoctoral training in brain science supported the study.

For more articles in this issue of Ophthalmology Times eReport, click here.

To receive weekly clinical news and updates in ophthalmology, subscribe to the Ophthalmology Times eReport.