Abstract
Introduction: :
Neuronal NOS (nNOS) is present in every cell type in the vertebrate retina and is used in many aspects of normal retinal function. In addition, nNOS has been associated with several pathologies of the eye including glaucoma and diabetic retinopathy. Neuronal NOS has several splice variants which can show altered expressions in specific pathological conditions. This study is aimed at determining which splice variants of nNOS are present in the mammalian retina.
Methods: :
Retinas were isolated from 3–5 week old mice and both RNA and protein were extracted. Protein extracts were used for western blot analysis while RNA was reverse transcribed and subjected to 5’ Rapid Amplification of cDNA Ends (5’RACE) to evaluate exon diversity at the 5’ end.
Results: :
Western blots show bands at the predicted sizes for nNOS alpha, beta, and gamma as well as bands at 70 and 50 KDa which have been reported previously. Densitometric analysis suggests that nNOS alpha is most abundant and nNOS gamma is least abundant. Results from the 5’RACE are consistent with the presence of nNOS alpha and beta.
Discussion: :
Taken together, these results show that at least four potentially functional splice variants are present in the mouse retina and that nNOS alpha seems to be the predominant variant in the retina, followed by beta and then gamma. Studies are in progress to evaluate these alternative expressions in retinal pathology.
Keywords: retina • nitric oxide • gene/expression