More Than Meets the Eye: Current Understanding of RPGR Function

  • Hemant KhannaEmail author
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1074)


This article summarizes the recent advances in our understanding of a major retinal disease gene RPGR (retinitis pigmentosa GTPase regulator), mutations in which are associated with majority of X-linked forms of retinal degenerations. A great deal of work has been done to uncover the ciliary localization of RPGR and its interacting proteins in the retina. However, the molecular mechanisms of action of RPGR in the photoreceptors are still unclear. Recent studies have begun to shed light on the intracellular pathways in which RPGR is likely involved. The deregulation of such pathways may underlie the pathogenesis of severe retinal degeneration associated with RPGR. With the recent advances in the gene augmentation therapy for RPGR-associated disease, there is a lot of excitement in the field. Patients with RPGR mutations, however, present with clinically heterogeneous manifestations. It is therefore imperative to examine the function of RPGR in detail, so that we can design patient-oriented therapeutic strategies for this disease.


RPGR Cilia Photoreceptor Ciliopathies RCC1 GTPase GEF Retinal degeneration X-linked retinitis pigmentosa Retinitis pigmentosa INPP5E PDE6δ Glutamylation Prenylation 



The work in my laboratory is supported by grants from the National Institutes of Health (EY022372) and Foundation Fighting Blindness.


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Ophthalmology and NeurobiologyUMASS Medical SchoolWorcesterUSA

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