Related Experiment Video
Updated: Aug 22, 2025
07:38
Quantifying the Activity of cis-Regulatory Elements in the Mouse Retina by Explant Electroporation
Published on: June 28, 2011
14.6K
Chromatin remodeler Chd7 regulates photoreceptor development and outer segment length.
Laura A Krueger1, Jessica D Bills1, Zun Yi Lim1
1Department of Biology, University of Kentucky, Lexington, KY, 40506-0225, USA.
Experimental Eye Research
|November 7, 2022
Summary
Chromatin remodeling factor CHD7 is crucial for retinal development and photoreceptor outer segment formation in zebrafish and mice. Loss of CHD7 function leads to microphthalmia and visual defects, offering insights into CHARGE syndrome pathogenesis.
Area of Science:
- Developmental Biology
- Genetics
- Ophthalmology
Background:
- Mutations in CHD7 cause CHARGE syndrome, a disorder often featuring ocular coloboma.
- The specific role of CHD7 in retinal development remains largely uninvestigated, despite visual impairment in CHARGE syndrome patients without coloboma.
Purpose of the Study:
- To investigate the expression pattern of Chd7 in developing zebrafish and mouse retinas.
- To characterize ocular and retinal phenotypes in Chd7 loss-of-function mutants.
Main Methods:
- Expression analysis of Chd7 in zebrafish and mouse retinas during development.
- Phenotypic characterization of zebrafish chd7 mutants and heterozygous Chd7 mutant mice.
Main Results:
- Chd7 is expressed in proliferating retinal progenitor cells and differentiating retinal neurons, including photoreceptors.
- Chd7 loss-of-function mutants exhibit microphthalmia, reduced cone photoreceptor numbers, and abnormal photoreceptor outer segments.
- Similar retinal defects, including reduced cone numbers and abnormal outer segments, are observed in heterozygous Chd7 mutant mice.
Conclusions:
- CHD7 plays a conserved role in retinal development and photoreceptor outer segment morphogenesis.
- This study highlights a potential mechanism for visual system defects in CHARGE syndrome.
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