Reduction of ETV1 is Identified as a Prominent Feature of Age-Related Cataract

Abstract

Purpose

To identify the inactive genes in cataract lenses and explore their function in lens epithelial cells (LECs).

Methods

Lens epithelium samples obtained from both age-related cataract (ARC) patients and normal donors were subjected to two forms of histone H3 immunoprecipitation: H3K9ac and H3K27me3 chromatin immunoprecipitation (ChIP), followed by ChIP-seq. The intersection set of “active genes in normal controls” and “repressed genes in cataract lenses” was identified. To validate the role of a specific gene, ETV1, within this set, quantitative polymerase chain reaction (qPCR), western blot, and immunofluorescence were performed using clinical lens epithelium samples. Small interference RNA (siRNA) was utilized to reduce the mRNA level of ETV1 in cultured LECs. Following this, transwell assay and western blot was performed to examine the migration ability of the cells. Furthermore, RNA-seq analysis was conducted on both cell samples with ETV1 knockdown and control cells. Additionally, the expression level of ETV1 in LECs was examined using qPCR under H₂O₂ treatment.

Results

Six genes were identified in the intersection set of “active genes in normal controls” and “repressed genes in ARC lenses”. Among these genes, ETV1 showed the most significant fold-change decrease in the cataract samples compared to the control samples. After ETV1 knockdown by siRNA in cultured LECs, reduced cell migration was observed, along with a decrease in the expression of β-Catenin and Vimentin, two specific genes associated with cell migration. In addition, under the oxidative stress induced by H₂O₂ treatment, the expression level of ETV1 in LECs significantly decreased.

Conclusions

Based on the findings of this study, it can be concluded that ETV1 is significantly reduced in human ARC lenses. The repression of ETV1 in ARC lenses appears to contribute to the disrupted differentiation of lens epithelium, which is likely caused by the inhibition of both cell differentiation and migration processes.

Keywords:

• Cataract
• lens capsule
• lens epithelial cells
• ETV1
• ChIP-seq

Acknowledgement

The RNA libraries were sequenced by OE Biotech, Inc., Shanghai, China. We are grateful to OE Biotech, Inc., (Shanghai, China) for assisting in sequencing and/or bioinformatics analysis.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The derived ChIP-seq data is available under request to the corresponding author D.L.