Dataset Information

Grk1b and Grk7a Both Contribute to the Recovery of the Isolated Cone Photoresponse in Larval Zebrafish.

ABSTRACT:

Purpose

To define the functional roles of Grk1 and Grk7 in zebrafish cones in vivo.

Methods

Genome editing was used to generate grk7a and grk1b knockout zebrafish. Electroretinogram (ERG) analyses of the isolated cone mass receptor potential and the b-wave were performed in dark-adapted zebrafish using a paired flash paradigm to determine recovery of cone photoreceptors and the inner retina after an initial flash. In addition, psychophysical visual response was measured using the optokinetic response (OKR).

Results

ERG analysis demonstrated that deletion of either Grk1b or Grk7a in zebrafish larvae resulted in modestly lower rates of recovery of the isolated cone mass receptor potential from an initial flash compared to wildtype larvae. On the other hand, grk1b-/- and grk7a-/- larvae exhibited a b-wave recovery that was similar to wildtype larvae. We evaluated the OKR and found that deletion of either Grk1b or Grk7a leads to a small decrease in temporal contrast sensitivity and alterations in visual acuity.

Conclusions

For the first time, we demonstrate that Grk1b and Grk7a both contribute to visual function in larval zebrafish cones. Since the difference between wildtype and each knockout fish is modest, it appears that either GRK is sufficient for adequate cone visual function.

SUBMITTER: Chrispell JD

PROVIDER: S-EPMC6203174 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Publications

Grk1b and Grk7a Both Contribute to the Recovery of the Isolated Cone Photoresponse in Larval Zebrafish.

Chrispell Jared D JD Dong Enheng E Osawa Shoji S Liu Jiandong J Cameron D Joshua DJ Weiss Ellen R ER

Investigative ophthalmology & visual science 20181001 12

<h4>Purpose</h4>To define the functional roles of Grk1 and Grk7 in zebrafish cones in vivo.<h4>Methods</h4>Genome editing was used to generate grk7a and grk1b knockout zebrafish. Electroretinogram (ERG) analyses of the isolated cone mass receptor potential and the b-wave were performed in dark-adapted zebrafish using a paired flash paradigm to determine recovery of cone photoreceptors and the inner retina after an initial flash. In addition, psychophysical visual response was measured using the ...[more]

PMID: 30372740

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Dataset Information

Grk1b and Grk7a Both Contribute to the Recovery of the Isolated Cone Photoresponse in Larval Zebrafish.

Purpose

Methods

Results

Conclusions

Publications

Grk1b and Grk7a Both Contribute to the Recovery of the Isolated Cone Photoresponse in Larval Zebrafish.

Similar Datasets

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