Bestrophin 2 is expressed in human non-pigmented ciliary epithelium but not retinal pigment epithelium.
OBJECTIVE
Mice in which bestrophin 2 (Best2) is disrupted exhibit changes in aqueous flow and drainage, resulting in a reduction in intraocular pressure in comparison to wild-type mice. Best2 encodes a putative anion channel localized uniquely to the basolateral plasma membrane of non-pigmented epithelium cells in mice. In this study, we examine the localization of Best2 in the human eye.


METHODS
Rabbit polyclonal antibodies recognizing human Best2 (hBest2) were generated and characterized for use in western blot, immunoprecipitation, and immunofluorescence assays. The expression of hBest2 using these antibodies was examined using human donor eye tissues.


RESULTS
We could not detect hBest2 in human ciliary bodies or other ocular tissues by western blot. However, when enriched by immunoprecipitation, hBest2 was identified in ciliary bodies, but not in the retinal pigment epithelium. Using immunofluorescence, we located hBest2 in the basolateral plasma membrane of non-pigmented epithelial cells.


CONCLUSIONS
We found expression of hBest2 similar to mice only in NPE cells. These data suggest that Best2 may play a functional role in the regulation of aqueous flow and drainage in humans. We conclude that Best2 represents a new potential target for glaucoma therapy.
Zhang
Youwen
Y
Department of Ophthalmology and Vision Science, University of Arizona, Tucson, AZ 85724, USA.
Patil
Rajkumar V
RV
Marmorstein
Alan D
AD
D000918:Antibody Specificity; D000075002:Bestrophins; D002460:Cell Line; D018118:Chloride Channels / Q000378:metabolism*; D002924:Ciliary Body / Q000378:metabolism*; D005136:Eye Proteins / Q000378:metabolism*; D006801:Humans; D047468:Immunoprecipitation; D010857:Pigment Epithelium of Eye / Q000378:metabolism*; D010858:Pigmentation; D021381:Protein Transport; D014019:Tissue Donors; D014162:Transfection
C465970:BEST2 protein, human; D000075002:Bestrophins; D018118:Chloride Channels; D005136:Eye Proteins