circGlis3 promotes β-cell dysfunction by binding to heterogeneous nuclear ribonucleoprotein F and encoding Glis3-348aa protein

作者：Xiong Li, Yingying Gong, Huashan Liu, Liang Huang, Ziwei Zeng, Xiaobin Zheng, Wenxin Li, Zhenxing Liang, Liang Kang · 发表于：iScience · 年份：2023 · DOI：10.1016/j.isci.2023.108680 · 被引用次数：7 · 研究领域：Circular RNAs in diseases、MicroRNA in disease regulation、RNA modifications and cancer

Circular RNAs (circRNAs) are crucial regulators of β-cell function and are involved in lipotoxicity-induced β-cell damage in type 2 diabetes mellitus (T2DM). We previously identified that circGlis3, a circRNA derived from exon 4 of the diabetes susceptibility gene Glis3 , was upregulated in lipotoxic β cells. However, the functional role and molecular mechanism of circGlis3 in β cells remain largely unknown. Here, we revealed that the splicing factor CUGBP Elav-Like Family Member 1 (CELF1) facilitated the biogenesis of circGlis3. Moreover, we established a transgenic mouse model and confirmed that the overexpression of circGlis3 impaired β-cell function. Mechanistically, circGlis3 bound to heterogeneous nuclear ribonucleoprotein F (hnRNPF) and blocked its nuclear translocation, thereby reducing Sirt1 levels. Additionally, circGlis3 encoded a 348aa protein that interacted with GLIS3 and inhibited its transcriptional activity. Our data uncover a critical role of circGlis3 in β-cell dysfunction, suggesting that circGlis3 may be a potential therapeutic target for T2DM.