Preserving the Precious Gift of Sight

Matthews Professorship

M D Matthews Professor

Bikash Pattnaik, PhD

Department of Pediatrics, Ophthalmology & Visual Sciences

University of Wisconsin

McPherson Eye Research Institute

Madison, WI


Dr. Pattnaik’s Research Project

Vision Loss Due to Ion-Channelopathy


Current Research Interests

Ion channelopathies are diseases caused by defective ion channels. Ion channels are membrane proteins distributed throughout the human body and mediate cell-cell communication through passage of specific ions into or out of cells. Patients with a specific potassium channel gene (KCNJ13, encoding Kir7.1 protein present in the Retinal Pigment Epithelium RPE) coding variants are diagnosed with a spectrum of blindness phenotypes: Snowflake Vitreoretinal Degeneration (SVD) and Lebers congenital Amaurosis (LCA).  Dr. Pattnaik has shown that a loss-of-function in the Kir7.1 channel disrupts RPE and photoreceptor cell communication using ectopic expressions and a mouse model that demonstrate pathological features in carriers.

RPE cells are retina glial cells that support our ability to see. Function of these RPE cells relies on the activity of ion channels and transporters confined to the membrane micro domain. Dr. Pattnaik is using small animal models, cell culture system and patient derived iPSC-RPE cells to understand cellular phenotypes. Any identifiable distinction between the control and diseased cells permit us to test efficacy of various therapeutic measures through “patient-in-a-dish” approach. Some of the experimental strategies his laboratory currently uses are small molecule drugs to overcome translational errors, or use of gene manipulation to measure Kir7.1 current through patch-clamp electrophysiology outcome.

Dr. Pattnaik’s future focus is on the basic understanding of the cellular basis of potassium and chloride channel function in the retina as tools to diagnose disease so as to develop its prevention.


7/1/2012 – 6/30/2016

Nansi Jo Colley, PhD

Department of Ophthalmology and Visual Sciences

Department of Genetics

University of Wisconsin,

Madison, WI


Dr. Colley’s Research Project

Molecular Genetic Studies of Retinal Degeneration in Drosophila

Current Research Interests

Dr. Colley is focused on using Drosophila as a model for studying hereditary human retinal diseases, such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD). An ongoing challenge in diagnosing and treating AMD and RP is that they are highly complex diseases with multiple subtypes, each with a distinct genetic and biochemical basis. This complexity, along with the limited availability of suitable tissues from RP and AMD patients and the broad base of knowledge of Drosophila genetics, all combine to make Drosophila a powerful animal model for studying inherited retinal degeneration disorders.

The proposed project will continue her focus on a novel Sec23-IP protein and its role in photoreceptor health and retinal degeneration. Dr. Colley’s laboratory has identified this novel locus as a retinal degeneration gene, which encodes a Sec23-Interacting Protein (Sec23-IP) and contains a signature of the Nir/rdgB family of proteins in flies and humans that is involved in retinal degeneration.

This year they will further characterize the role of the Drosophila Sec23-IP in the secretory pathway. In a comprehensive analysis, they will study the role of Sec23-IP in the transport of the major rhodopsin (Rh1), how defects in Sec23-IP lead to retinal degeneration. The Drosophila Sec23-IP displays 49% identity with the human Sec23-IP. Studies proposed here will provide insights into the basis of Nir/rdgB function in humans.

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Mission of RRF

The mission of the Retina Research Foundation is to reduce retinal blindness worldwide by funding programs in research and education. As a public charity, RRF raises funds from the private sector and the investment of its endowment funds.

RRF’s 48th Anniversary

October 1, 2017