Primate short-wavelength cones share molecular markers with rods.

Macaca, Callithrix jacchus marmoset monkey, Pan troglodytes chimpanzee and human retinas were examined to define if short wavelength (S) cones share molecular markers with L&M cone or rod photoreceptors. S cones showed consistent differences in their immunohistochemical staining and expression levels compared to L&M cones for "rod" Arrestin1 (S-Antigen), "cone" Arrestin4, cone alpha transducin, and Calbindin. Our data verify a similar pattern of expression in these primate retinas and provide clues to the structural divergence of rods and S cones versus L&M cones, suggesting S cone retinal function is "intermediate" between them.

Localizations of visual cycle components in retinal pigment epithelium.

Purpose: We used immunocytochemistry and confocal microscopy to determine whether enzymes of the rod visual cycle were uniformly distributed in retinal pigment epithelium (RPE) cells. The localizations of these enzymes were compared to known localizations of retinoid-binding proteins and associated proteins.

Methods: Antibodies to proteins and enzymes associated with the rod visual cycle were used for fluorescence immunocytochemistry with frozen sections of albino mouse and rat retina.

Human orbital sympathetic nerve pathways.

Purpose: To determine pathways of sympathetic nerves from the orbital apex to the eyelids in human cadaver tissue using immunohistochemistry.

Methods: Human cadaver orbit tissue was sectioned and immunolabeled with a monoclonal antityrosine hydroxylase antibody.

Results: In the orbital apex, the nasociliary, frontal, lacrimal, and maxillary branches of the trigeminal nerve demonstrated intense staining upon entering the orbit.

The zinc-binding domain of Nna1 is required to prevent retinal photoreceptor loss and cerebellar ataxia in Purkinje cell degeneration (pcd) mice.

The Purkinje cell degeneration (pcd) mouse undergoes retinal photoreceptor degeneration and Purkinje cell loss. Nna1 is postulated to be the causal gene for pcd. We show that a BAC containing the Nna1 gene rescues retinal photoreceptor loss and Purkinje cell degeneration, confirming that Nna1 loss-of-function is responsible for these phenotypes.

Cellular debris and ROS in age-related cortical cataract are caused by inappropriate involution of the surface epithelial cells into the lens cortex.

Purpose: To quantify changes in the lens epithelial cells and underlying lens cortex responsible for age-related cortical cataract (ARCC) in the rat.

Methods: Freshly isolated lenses were stained vitally for DNA with Hoechst 33342. Reactive oxygen species (ROS) and mitochondria were visualized and quantified by dihydrorhodamine 123 (DHR).

Essential role of Ca2+-binding protein 4, a Cav1.4 channel regulator, in photoreceptor synaptic function.

CaBP1-8 are neuronal Ca(2+)-binding proteins with similarity to calmodulin (CaM). Here we show that CaBP4 is specifically expressed in photoreceptors, where it is localized to synaptic terminals. The outer plexiform layer, which contains the photoreceptor synapses with secondary neurons, was thinner in the Cabp4(-/-) mice than in control mice.

Cellular retinaldehyde-binding protein interacts with ERM-binding phosphoprotein 50 in retinal pigment epithelium.

Purpose: To characterize mechanisms of apical localization of visual cycle components in retinal pigment epithelium (RPE) by the identification of cellular retinaldehyde-binding protein (CRALBP) interaction partners.

Methods: An overlay assay was used to detect interactions of CRALBP with components of RPE microsomes. Interacting proteins were identified with two-dimensional (2D)-PAGE and liquid chromatography tandem mass spectrometry (LC MS/MS).

Development of genetically engineered tet HPV16-E6/E7 transduced human corneal epithelial clones having tight regulation of proliferation and normal differentiation.

Lack of an optimal in vitro model of human corneal epithelial (HCE) cells is a major limitation in studying normal functions and gene regulations in HCE. Moreover, availability of a multi-layered HCE culture can reduce the usage of animals in the toxicity testing of consumer products. We have developed tetracycline-responsive human papilloma virus (HPV) 16-E6/E7 transduced HCE clones showing tight regulation of proliferation and normal differentiation.

Polyglutamine-expanded ataxin-7 promotes non-cell-autonomous purkinje cell degeneration and displays proteolytic cleavage in ataxic transgenic mice.

Spinocerebellar ataxia (SCA) type 7 is an inherited neurodegenerative disorder caused by expansion of a polyglutamine tract within the ataxin-7 protein. To determine the molecular basis of polyglutamine neurotoxicity in this and other related disorders, we produced SCA7 transgenic mice that express ataxin-7 with 24 or 92 glutamines in all neurons of the CNS, except for Purkinje cells. Transgenic mice expressing ataxin-7 with 92 glutamines (92Q) developed a dramatic neurological phenotype presenting as a gait ataxia and culminating in premature death.