Breakthrough in Blindness

Dr. Jeffrey Y H Chung numbRecently, there has been a major scientific breakthrough by a group of scientists in Montreal, who have discovered that a protein found in the retina plays an essential role in the function and survival of light-sensing cells that are necessary for vision.  Such findings could have a huge impact on our understanding of retinal degenerative diseases that cause blindness.  The researchers studied compartmentalization, a process which establishes and maintains different compartments within a cell, each of which contains a specific set of proteins.  Such a process is essential for neurons to function properly.

The compartments within a cell are like the different parts of a car; in the same way that gas must be in the fuel tank to power the car’s engine, proteins need to be in a specific compartment to properly exercise their functions.  One good example of compartmentalization can be observed in a specialized type of light-sensing neurons in the retina, the photoreceptors, which are made up of different compartments containing specific proteins essential for vision.  The researchers wanted to understand how compartmentalization is achieved within photoreceptor cells, and their work seems to have identified a new mechanism that would explain this process.  More specifically, the researchers found that a specific protein known as Numb functions like a traffic controller to direct proteins to the appropriate compartments.

The researchers demonstrated that without Numb, photoreceptors are unable to send a molecule essential for vision to the correct compartment, which causes the cells to progressively degenerate and die.  The death of photoreceptor cells is known to cause retinal degenerative diseases in humans that ultimately lead to blindness, and the researchers’ work therefore helps to provide a new piece of the puzzle to help scientists better understand how and why cells die.  Such results could lead to a substantial impact on the development of treatments for retinal degenerative diseases, such as Leber’s congenital amaurosis and retinitis pigmentosa, by providing novel drug targets to prevent photoreceptor degeneration.