Localization of nyctalopin in the mammalian retina.
Complete X-linked congenital stationary night blindness (CSNB1) is a hereditary visual disease characterized by abnormalities in both the dark- and light-adapted electroretinogram, consistent with a defect in synaptic transmission between photoreceptors and ON-bipolar cells. The gene responsible for CSNB1, NYX, encodes a novel, leucine-rich repeat protein, nyctalopin. Consistent with its predicted glycosylphosphatidylinositol linkage, we show that recombinant nyctalopin is targeted to the extracellular cell surface in transfected HEK293 cells. Within the retina, strong nyctalopin immunoreactivity is present in the outer plexiform layer, the site of the photoreceptor to bipolar cell synapses. Double labelling of nyctalopin and known synaptic proteins in the outer plexiform layer indicate that nyctalopin is associated with the ribbon synapses of both rod and cone terminals. In the inner plexiform layer, nyctalopin immunoreactivity is associated with rod bipolar cell terminals. Our findings support a role for nyctalopin in synaptic transmission and/or synapse formation at ribbon synapses in the retina.
Neurological Sciences Institute, Oregon Health and Science University, Beaverton, 97006, USA. morgansc@ohsu.edu
Catherine W
CW
Morgans
Gaoying
G
Ren
Lakshmi
L
Akileswaran
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D006801:Humans; D008251:Macaca; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D011509:Proteoglycans / Q000032:analysis* / Q000235:genetics; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000737:chemistry* / Q000166:cytology; D013569:Synapses / Q000737:chemistry / Q000648:ultrastructure; D009435:Synaptic Transmission
C416505:NYX protein, human; D011509:Proteoglycans