Cell Biology of NMB in Pigmentary Glaucoma

DBA/2J mice are an animal model of pigment dispersion syndrome (PDS), which is a precursor to glaucoma in humans. These mice are thought to have a loss-of-function mutation in the NMB gene that is responsible for this disease. Dr. Theos and colleagues are proposing experiments that will characterize the NMB protein within pigmented cells of the eye in order to understand how NMB functions in normal cells, and, in addition, how loss of function of NMB causes PDS.

Dr. Theos and colleagues will look at the cells in the eye that produce the pigment that gives the iris its color. These cells die as a prelude to the development of a type of inherited glaucoma known as pigmentary glaucoma (PG). Unfortunately, very little is known about why these particular cells within the eye do not survive with age and cause problems that lead to the disease. These researchers will use cells from the eyes of DBA/2J mice that develop PDS to test if a specific protein, called NMB, is important for keeping the cells healthy by making and storing these pigments within the confines of a specialized cell compartment. To get a handle on this, the researchers will first determine if the normal protein is in the right place within cells to carry out this type of function.

The results of this research may have an impact on other devastating diseases, as NMB has recently been shown to be critically important not only in PG, but also in a rare but devastating cancer of the eye called uveal melanoma. If Theos and colleagues can fully understand how NMB leads to changes in the behavior of eye cells, this will help to develop new therapies to correct the problem or even prevent the development of these debilitating diseases.