Potential cellular functions of N-ethylmaleimide sensitive factor in the photoreceptor

Abstract

N-ethylmaleimide sensitive factor (NSF) is an ATPase associated with a variety of cellular activities in the AAA protein family and is required for intracellular membrane fusion. We reported a novel synaptic protein-protein interaction between visual Arrestin 1 (Arr1) and NSF that is enhanced in a dark environment when photoreceptors are depolarized and the rate of exocytosis is elevated. In the photoreceptor synapse, NSF functions to sustain a tonic rate of exocytosis, in addition to the compensatory endocytosis to retrieve and to recycle vesicle membrane and synaptic proteins. In addition to the Arr1 and NSF interaction, NSF was shown to interact with the retinitis pigmentosa protein 2 (RP2) in the retina and may play an important role in membrane protein trafficking in photoreceptors. These studies demonstrate diverse roles of NSF in the photoreceptor synapse and in membrane protein trafficking and provide key insights into the potential molecular mechanisms of inherited retinal diseases, such as Oguchi disease and retinitis pigmentosa. © 2012 Springer Science+Business Media, LLC.