University of Houston Researchers Awarded $3.6M to Investigate Vision-Critical Gene

A team of endowed professors and vision scientists at the University of Houston has been awarded more than $3.6 million from the National Eye Institute (NEI) to investigate a gene essential for normal vision but, when mutated, linked to a wide range of retinal diseases that can lead to blindness.

The gene in focus, peripherin 2 (PRPH2), encodes a protein that plays a critical role in shaping the outer segments of photoreceptor cells—rods and cones—within the retina. These light-sensitive structures are responsible for capturing visual information and converting it into the electrical signals the brain interprets as images.

When functioning normally, PRPH2 is vital to healthy vision. But more than 300 known mutations in the gene can trigger a spectrum of degenerative retinal conditions. These include retinitis pigmentosa, pattern dystrophy, cone-rod dystrophy, and several forms of macular degeneration. Despite the clinical impact, the mechanisms underlying PRPH2-related pathology remain poorly understood.

“We want to understand how defects with the PRPH2 gene lead to eye diseases. Our main objective is to uncover the mechanisms underlying PRPH2-associated pathology, with a focus on its roles in rods and cones, the two types of photoreceptor cells in the retina,” said Muna Naash, PhD, John S. Dunn Endowed Professor of Biomedical Engineering at the University of Houston.

Her research partner, Muayyad Al-Ubaidi, PhD, John & Rebecca Moores Professor of Biomedical Engineering, added: “We will also examine how these cells are built and organized, and how proteins are transported to their outer segments.”

Given the number of disease-causing mutations, PRPH2 has become an important target for gene therapy. However, current options are limited.

“Despite considerable scientific advancement, there are still no clinically viable therapeutic options for PRPH2 retinal diseases,” said Al-Ubaidi. “Gaining a thorough grasp of the mechanisms associated with PRPH2 diseases is crucial for designing effective therapies.”

To bridge these gaps, Drs. Naash and Al-Ubaidi developed experimental models and therapeutic platforms designed to evaluate disease mechanisms and test potential treatments. The team will place particular emphasis on PRPH2’s biochemical properties and its interaction with retinal outer segment membrane protein 1 (ROM1). By focusing on these interactions, the researchers hope to unravel how PRPH2 contributes to the formation of rod and cone outer segment rims—an area that has long remained elusive for scientists.

“This will aid our understanding of the precise mechanisms governing PRPH2's involvement in rod and cone outer segment rim formation, an elusive goal that has long hindered the development of effective therapies,” Dr. Naash said.