Zebrafish: An In Vivo Screening Model to Study Ocular Phenotypes

Abstract

Purpose To establish a set of assays that allow the in vivo screening of candidate genes for ocular diseases in zebrafish, with an emphasis on refractive error. Methods Our pipeline includes the most relevant ocular screening measurements to assess (1) ocular biometry using spectral domain optical coherence tomography, (2) refractive status using an eccentric photorefractor, (3) intraocular pressure by tonometry, and (4) optokinetic response to study visual capability in zebrafish. To validate our pipeline and to demonstrate the potential of zebrafish as a valid animal model, we chose two well-characterized genes with an ocular phenotype ( PRSS56 and FBN1 ) and generated two mutant zebrafish lines ( prss56 and fbn1 ). Mutant fish were assessed at 2, 4, and 6 months after fertilization. Results With the proposed phenotyping pipeline, we showed that ocular biometry, refractive status, intraocular pressure, and visual function can be studied in zebrafish. In the prss56 mutant, the pipeline revealed a dramatic decrease in axial length, mainly owing to a decreased vitreous chamber depth, whereas in the fbn1 mutant, ectopia lentis was the most distinctive ocular phenotype observed. Tonometry in both mutant lines showed an increase in intraocular pressure. Conclusions The proposed pipeline was applied successfully in zebrafish and can be used for future genetic screenings of candidate genes. While validating our pipeline, we found a close resemblance between the ocular manifestations in the zebrafish mutants and patients harboring mutations in PRSS56 and FBN1 . Our results support the validity of our pipeline and highlight the potential of zebrafish as an animal model for in vivo screening of candidate genes for ocular diseases.

Post-GWAS screening of candidate genes for refractive error in mutant zebrafish models

“…5 , Supplementary Data S5 ). This has also been found in previous studies, and has mainly been attributed to the small eye retinoscopic artifact 7 , 8 , 17 – 19 . In agreement with our biometric data, a myopic shift in refractive status was found at 2 mpf for lrrc4ca re17 lrrc4cb re18 (effect size = − 3.4D, p < 0.0001) and for kcnq5a re19 kcnq5b re20 (effect size = − 2.4D, p = 0.003) relative to WT controls (Fig.…”

“…To explore whether the changes in axial length resulted in alterations in refractive status, a custom eccentric photorefraction set-up was used as described previously 7 , 8 . The WT control fish (n = 20 eyes) showed a positive baseline refractive status (Fig.…”

“…The goal of this functional study is to evaluate the potential of candidate RE genes in controlling refractive error using zebrafish (Danio rerio) as a model. We have previously demonstrated that the zebrafish is an efficient model to study RE 7 , 8 , which offers a significant improvement in time and costs compared to the more traditionally used avian or mammalian animal models. Using zebrafish, we have previously shown that depletion of GJD2 (located in one of the genome-wide top-associated signals) leads to the development of RE 8 .…”

A Novel High-Content Screening Assay Identified Belinostat as Protective in a FSGS—Like Zebrafish Model

“…32 In current zebrafish in vivo HCS assays, quality metrics beside signal-to-noise ratios are barely reported. 29,33–36…”

“…32 In current zebrafish in vivo HCS assays, quality metrics beside signal-to-noise ratios are barely reported. 29,[33][34][35][36] In the past, epigenetic changes have been shown to play an important role in kidney cell biology and disease. 37,38 It is notable that histone deacetylases (HDACs) are known to play a pivotal role in kidney injury and are an interesting pharmacologic target in podocytes.…”