RNA-seq analysis of circRNA profiles in the lens of Crybb2 knockout mice

Abstract

\n Background: Currently, there is little information on the expression profiles of circRNAs in the lens. βB2-crystallin (CRYBB2) is an abundant protein in the mammalian lens, and its abnormal expression contributes to the development of cataract. This study aimed at exploring how Crybb2 knockout could modulate the expression profiles of circRNAs in mouse lens. Methods and Results: We extracted total RNAs from the lens of wide-type (WT) and Crybb2 -/- mice and after depleted their rRNAs and broken the remaining RNAs, we reversely transcribed the RNAs into cDNAand sequenced them. Furthermore, we performed bioinformatics to identify and analyze the differentially expressed circRNAs and predicted their potential functions. We validated some differentially expressed circRNAs by quantitative RT-PCR. We employed RNA-seq to identify 49,494 circRNAs and compared to the WT lens, 149 circRNAs were upregulated and 172 downregulated in Crybb2 -/- mouse lens. With the top 300 miRNA-circRNA interaction pairs, we constructed a network of circRNA-miRNA interactions. Moreover, those differentially expressed circRNAs participated in various biological processes, such as lens fiber cell development, calcium channel complex, structural constituent of the lens. They were involved in several important pathways, such as the canonical Wnt signaling pathway. Quantitative RT-PCR validated some differently expressed circRNAs in the lens of Crybb2 -/- mice. Conclusions: Crybb2 knockout significantly modulated circRNA expression profiles in the lens of mice, which may help clarify the roles of circRNAs in age-related cataracts.