DOI: 10.5061/dryad.zs7h44jd9
title: Data for: Impact of alpha crystallin loss on zebrafish lens development

description: The α-crystallin small heat shock proteins contribute to the transparency
 and refractive properties of the vertebrate eye lens and prevent the
 protein aggregation that would otherwise produce lens cataracts, the
 leading cause of human blindness. There are conflicting data in the
 literature as to what role the α-crystallins may play in early lens
 development. In this study, we used CRISPR gene editing to produce
 zebrafish lines with mutations in each of the three a-crystallin genes
 (cryaa, cryaba and cryabb) to prevent protein production. The absence of
 each α-crystallin protein was analyzed by mass spectrometry, and lens
 phenotypes were assessed with differential interference contrast
 microscopy and histology. Loss of αA-crystallin produced a variety of lens
 defects with varying severity in larval lenses at 3 and 4 dpf but little
 substantial change in normal fiber cell denucleation. Loss of
 αBa-crystallin produced no substantial lens defects. Our cryabb mutant
 produced a truncated aBb-crystallin protein and showed no substantial
 change in lens development. Mutation of each α-crystallin gene did not
 alter the mRNA levels of the remaining two, suggesting a lack of genetic
 compensation. These data suggest that αA-crystallin plays some role in
 lens development, but the range of phenotype severity in null mutants
 indicates its loss simply increases the chance for defects and that the
 protein is not essential. Our finding that cryaba and cryabb mutants lack
 noticeable lens defects is congruent with insubstantial transcript levels
 for these genes in lens epithelial and fiber cells through five days of
 development. Future experiments can explore the molecular mechanisms
 leading to lens defects in cryaa null mutants and the impact of
 αA-crystallin loss during zebrafish lens aging.
description: This dataset includes micrographs of the gross anatomy of
 PTU-treated zebrafish larvae and differential interference contrast
 microscopy of their eyes showing the lens. Included are sets of images at
 3 and 4 days post fertilization of wild type fish, mutants for three
 α-crystallin genes (<em>cryaa</em>,
 <em>cryaba</em> and <em>cryabb</em>) and crispants
 for <em>cryaa</em>. All larvae were imaged at 45X total
 magnification and eyes at 200X total magnification. Also included are
 images of stage micrometers photographed at each magnification. These
 micrometer images were used to measure total larval length and lens
 diameter for all images. These images were used to
 analyze lens size versus body length and to quantify the presence of lens
 defects, found in figures 4 and 5 in the linked manuscript. Three data
 seta do not contain images of larvae and were only used to quantify
 presence of lens defects: “112221 cryaa 3 dpf”, “102620 crispants 3 dpf”
 and “121421 crispants 4 dpf”. Quantified data and R scripts used to
 analyze these images can be found in the following GitHub repository:
 github.com/masonfromohio/alpha-crystallin-CRISPR-Rscripts
description: All image files are found as TIFF files and can be opened in any
 image viewer or editor. Larval length and eye lens diameters were measured
 using ImageJ and analyzed with R. The R scripts used to analyze these
 images can be found in the following GitHub repository: github.com/masonfromohio/alpha-crystallin-CRISPR-Rscripts