Evidence map›Paper›PMID 26664249›Full record

ArticleMolecular vision2015

The retinal phenotype of Grk1-/- is compromised by a Crb1 rd8 mutation.

Joseph S Pak, Eun-Jin Lee, Cheryl Mae Craft

Open access · greenAbstract read
In one paragraph

Article in Molecular vision, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers.

0numbers the graph read from it
0cells of the map it votes in
7citing papers in PubMed
0.3field-weighted citation impact, top 37% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

7 citing papers in PubMed, 12 citations in OpenAlex.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors at 1 institution in 1 country.

Joseph S PakMary D. Allen Laboratory for Vision Research, USC Eye Institute, Departments of Ophthalmology and Cell & Neurobiology, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
Eun-Jin LeeMary D. Allen Laboratory for Vision Research, USC Eye Institute, Departments of Ophthalmology and Cell & Neurobiology, Keck School of Medicine of the University of Southern California, Los Angeles, CA ; Department of Biomedical Engineering, University of Southern California Viterbi School of Engineering, CA.
Cheryl Mae CraftMary D. Allen Laboratory for Vision Research, USC Eye Institute, Departments of Ophthalmology and Cell & Neurobiology, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
University of Southern California · US

Funding

VISION RESEARCHP30EY003040 · NEI · DOHENY EYE INSTITUTE · PI SUN, DEMING · 1985 to 2013
$7.0M
Mechanisms of Cone Pigment DeactivationR01EY015851 · NEI · UNIVERSITY OF SOUTHERN CALIFORNIA · PI CRAFT, CHERYL MAE · 2005 to 2009
$1.8M
NEI NIH HHS P30 EY003040NEI NIH HHS P30EY03040NEI NIH HHS R01 EY015851NEI NIH HHS R01EY015851
6 · The paper itself

Abstract

purposeWell-established laboratory mouse lines are important in creating genetically engineered knockout mouse models; however, these routinely used inbred strains are prone to spontaneous and deleterious mutations. One of these strains, the commonly used C57BL/6N (B6N), was discovered to carry a point mutation in the Crumbs homolog 1 (Crb1(rd8) ) gene, which codes for a developmental protein involved in tight junction formation at the outer limiting membrane (OLM). This mutation disrupts photoreceptor polarity and leads to retinal degeneration. It was hypothesized that the G-protein receptor kinase 1 knockouts (Grk1(-/-) ), which were based on the B6N strain, would exhibit abnormal morphological phenotypes in their offspring not related to GRK1's major phosphorylation function. The hypothesis was tested by examining Grk1(-/-) with or without the Crb1(rd8) mutation.

methodsThe mice strains tested were C57BL/6J (B6J), B6N, and Grk1(-/-) on either a B6J (Grk1(-/-) (;B6J)) or B6N background (Grk1(-/-) (;B6N)) and were verified with PCR genotype analysis for Grk1(-/-) and Crb (rd8) . The mice were bred and raised in complete darkness until 1 or 3 months of age and then exposed to 1,000 lux light for 24 h, followed by processing for immunohistochemistry (IHC) analysis on the retinal structure to investigate the morphological effects of light exposure. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) was performed to detect photoreceptor apoptosis.

resultsThe microanatomy of the retinal sections revealed disorganization of the outer nuclear layer (ONL) in the B6N and Grk1(-/-) (;B6N) mice and a significant decrease in the thickness of the ONL in the 3-month-old Grk1(-/-) (;B6N) mice. The adherens-junction-associated protein, Zona occludens-1 (ZO-1), formed a continuous line at the OLM in the 1- and 3-month-old control B6J and Grk1(-/-) (;B6J) mice. In contrast, the B6N and Grk1(-/-) (;B6N) retinas showed discontinuous and fragmented staining for ZO-1 at the OLM at both ages. After the mice were exposed to light, TUNEL analysis showed a significant increase in photoreceptor cell death in the Grk1(-/-) (;B6J) and Grk1(-/-) (;B6N) retinas versus either the B6J or B6N retinas at 1 and 3 months of age and a small significant difference between the Grk1(-/-) (;B6J) and Grk1(-/-) (;B6N) retinas at 1 month. In addition, glial fibrillary acidic protein (GFAP) expression was enhanced in the Grk1(-/-) (;B6J) and Grk1(-/-) (;B6N) retinas at 1 and 3 months. Occasional sprouting processes of rod bipolar cells were detected in the B6N and Grk1(-/-) (;B6N) retinas, but sprouting was not detected in the B6J or Grk1(-/-) (;B6J) retinas at either age.

conclusionsThe B6N strain background exhibited abnormal phenotypes in the Grk1(-/-) (;B6N) retina. This study demonstrates that the B6N background can influence the phenotype of a genetic mouse knockout and introduces potential visual functional consequences of the Crb1 mutation.

Indexed as

PhenotypeAge FactorsAnimalsApoptosisDarknessFemaleGene Expression RegulationGlial Fibrillary Acidic ProteinG-Protein-Coupled Receptor Kinase 1In Situ Nick-End LabelingMaleMiceMice, Inbred C57BLMice, KnockoutMutationNerve Tissue ProteinsCrb1 protein, mouseGlial Fibrillary Acidic Proteinglial fibrillary astrocytic protein, mouseG-Protein-Coupled Receptor Kinase 1Grk1 protein, mouseNerve Tissue ProteinsTjp1 protein, mouseZonula Occludens-1 Protein

Identifiers

PMID26664249
PMCPMC4663191
OpenAlexW2188796122

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LicenceCC BY-NC-ND
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.