返回
A New Zebrafish Model for CACNA2D4-Dysfunction
DOI:10.1167/iovs.19-26759.png)
摘要
En 中文
PURPOSE. Mutations in CACNA2D4, encoding the alpha(2)delta(4) subunit of retinal voltage-gated calcium channels (Ca-v), cause a rare type of retinal dysfunction in human, mainly affecting cone vision. Here, we investigate the role of CACNA2D4 in targeting of Ca-v, its influence on cone-mediated signal transmission, and the cellular and subcellular changes upon loss of alpha(2)delta(4) by exploiting the advantages of the cone-dominant zebrafish as model system. METHODS. We identified two zebrafish CACNA2D4 paralogs (cacna2d4a and cacna2d4b), analyzed their expression by RNA in situ hybridization and introduced truncating frameshift mutations through CRISPR/Cas9-mediated mutagenesis. We analyzed retinal function and morphology of the single and double mutant lines by electroretinography, immunohistochemistry, light- and electron microscopy. RESULTS. Knockout of cacna2d4b reduces the expression of Cacna1fa, the pore-forming subunit of retinal Ca(v)1.4, whereas loss of cacna2d4a did not. Only knockout of both paralogs impaired cone-mediated ERG b-wave amplitude. The number of floating'' ribbons is increased in double-KO, while retinal morphology and expression of postsynaptic mGluR6b remain largely unaffected. Both Cacna1fa and Ribeyeb show ectopic punctate expression in cacna2d4b-KO and double-KO photoreceptors. CONCLUSIONS. We find that increasing the expression of Ca-v at the synaptic membrane is an evolutionarily conserved function of Cacna2d4b. Yet, since both paralogs participate in cone synaptic transmission, we propose partial subfunctionalization in zebrafish. Similar to human patients, our double KO zebrafish model shows mild cone dysfunction, which was not associated with signs of retinal degeneration. Therefore, cacna2d4-KO zebrafish is a suitable model to study the pathophysiological mechanisms underlying CACNA2D4 dysfunction in human.
Keyword:
calcium channel
cone photoreceptor
zebrafish
disease model
AI总结
对已上传原文的论文进行重点信息的提取,主要内容包括:简要概述、研究摘要、背景介绍、关键亮点、图文解析、展望与总结。
期刊
I
IF:
4.7
论文数:
1.7W
被引数:
5.5W
机构
引用论文
Functional exofacially tagged N-type calcium channels elucidate the interaction with auxiliary α2δ-1 subunits功能性表面外标记的N型钙通道阐明了与辅助 α2δ-1亚基的相互作用
Mutation in the auxiliary calcium-channel subunit CACNA2D4 causes autosomal recessive cone dystrophy
Direct imaging of uncoated biological samples enables correlation of super-resolution and electron microscopy data未经涂覆的生物样品的直接成像可实现超分辨率和电子显微镜数据的关联
SCIENTIFIC REPORTS
IF3.9
Loss-of-function mutations in a calcium-channel α1-subunit gene in Xp11.23 cause incomplete X-linked congenital stationary night blindness
NATURE GENETICS
IF31.8
Zebrafish Cacna1fa is required for cone photoreceptor function and synaptic ribbon formation斑马鱼Cacna1fa是视锥细胞光感受器功能和突触带形成所必需的

