Back to Search
Start Over
Arrestin 1 and Cone Arrestin 4 Have Unique Roles in Visual Function in an All-Cone Mouse Retina
- Source :
- Investigative Opthalmology & Visual Science. 56:7618
- Publication Year :
- 2015
- Publisher :
- Association for Research in Vision and Ophthalmology (ARVO), 2015.
-
Abstract
- PURPOSE Previous studies discovered cone phototransduction shutoff occurs normally for Arr1-/- and Arr4-/-; however, it is defective when both visual arrestins are simultaneously not expressed (Arr1-/-Arr4-/-). We investigated the roles of visual arrestins in an all-cone retina (Nrl-/-) since each arrestin has differential effects on visual function, including ARR1 for normal light adaptation, and ARR4 for normal contrast sensitivity and visual acuity. METHODS We examined Nrl-/-, Nrl-/-Arr1-/-, Nrl-/-Arr4-/-, and Nrl-/-Arr1-/-Arr4-/- mice with photopic electroretinography (ERG) to assess light adaptation and retinal responses, immunoblot and immunohistochemical localization analysis to measure retinal expression levels of M- and S-opsin, and optokinetic tracking (OKT) to measure the visual acuity and contrast sensitivity. RESULTS Study results indicated that Nrl-/- and Nrl-/-Arr4-/- mice light adapted normally, while Nrl-/-Arr1-/- and Nrl-/-Arr1-/-Arr4-/- mice did not. Photopic ERG a-wave, b-wave, and flicker amplitudes followed a general pattern in which Nrl-/-Arr4-/- amplitudes were higher than the amplitudes of Nrl-/-, while the amplitudes of Nrl-/-Arr1-/- and Nrl-/-Arr1-/-Arr4-/- were lower. All three visual arrestin knockouts had faster implicit times than Nrl-/- mice. M-opsin expression is lower when ARR1 is not expressed, while S-opsin expression is lower when ARR4 is not expressed. Although M-opsin expression is mislocalized throughout the photoreceptor cells, S-opsin is confined to the outer segments in all genotypes. Contrast sensitivity is decreased when ARR4 is not expressed, while visual acuity was normal except in Nrl-/-Arr1-/-Arr4-/-. CONCLUSIONS Based on the opposite visual phenotypes in an all-cone retina in the Nrl-/-Arr1-/- and Nrl-/-Arr4-/- mice, we conclude that ARR1 and ARR4 perform unique modulatory roles in cone photoreceptors.
- Subjects :
- Retinal degeneration
Opsin
Light Signal Transduction
genetic structures
Arrestins
Immunoblotting
Biology
Retinal Cone Photoreceptor Cells
Mice
Electroretinography
Arrestin
medicine
Animals
Vision, Ocular
Mice, Knockout
Retina
Microscopy, Confocal
medicine.diagnostic_test
Retinal Degeneration
Rod Opsins
Biochemistry and Molecular Biology
Anatomy
medicine.disease
Immunohistochemistry
eye diseases
Cell biology
Mice, Inbred C57BL
Disease Models, Animal
Phenotype
medicine.anatomical_structure
sense organs
Photopic vision
Visual phototransduction
Subjects
Details
- ISSN :
- 15525783
- Volume :
- 56
- Database :
- OpenAIRE
- Journal :
- Investigative Opthalmology & Visual Science
- Accession number :
- edsair.doi.dedup.....a7d53dc22ce7b1ccf304d15d9b04bc78