Eye Hospital, The First Affiliated Hospital of Harbin Medical University, Harbin, 150000, China.
Department of Urology, Shengjing Hospital of China Medical University, Shenyang, 110004, China.
J Transl Med. 2024 May 19;22(1):476. doi: 10.1186/s12967-024-05287-4.
Diabetic retinopathy (DR) is the leading cause of blinding eye disease among working adults and is primarily attributed to the excessive proliferation of microvessels, which leads to vitreous hemorrhage and retinal traction, thereby significantly impairing patient vision. NSUN2-mediated RNA mC methylation is implicated in various diseases, and in this investigation, we focused on elucidating the impact of NSUN2 on the regulation of the expression of the downstream gene MUC1, specifically through RNA mC methylation, on the progression of DR.
Utilizing Microarray analysis, we examined patient vitreous fluid to pinpoint potential therapeutic targets for DR. Differential expression of NSUN2 was validated through qRT-PCR, Western blot, and immunofluorescence in human tissue, animal tissue, and cell model of DR. The relationship between NSUN2 and DR was explored in vitro and in vivo through gene knockdown and overexpression. Various techniques, such as MeRIP-qPCR and dot blot, were applied to reveal the downstream targets and mechanism of action of NSUN2.
The levels of both NSUN2 and RNA mC methylation were significantly elevated in the DR model. Knockdown of NSUN2 mitigated DR lesion formation both in vitro and in vivo. Mechanistically, NSUN2 promoted MUC1 expression by binding to the RNA mC reader ALYREF. Knockdown of ALYREF resulted in DR lesion alterations similar to those observed with NSUN2 knockdown. Moreover, MUC1 overexpression successfully reversed a series of DR alterations induced by NSUN2 silencing.
NSUN2 regulates the expression of MUC1 through ALYREF-mediated RNA mC methylation, thereby regulating the progression of DR and providing a new option for the treatment of DR in the future.
糖尿病视网膜病变（DR）是导致成年工作人群失明的主要原因，主要是由于微血管过度增殖，导致玻璃体出血和视网膜牵引，从而显著损害患者的视力。NSUN2 介导的 RNA mC 甲基化与多种疾病有关，在这项研究中，我们专注于阐明 NSUN2 通过 RNA mC 甲基化对下游基因 MUC1 表达的调节作用，特别是对 DR 进展的影响。
我们利用微阵列分析，研究了患者的玻璃体液，以确定 DR 的潜在治疗靶点。通过 qRT-PCR、Western blot 和免疫荧光在人组织、动物组织和 DR 细胞模型中验证了 NSUN2 的差异表达。通过基因敲低和过表达在体外和体内研究了 NSUN2 与 DR 的关系。应用 MeRIP-qPCR 和斑点印迹等各种技术揭示了 NSUN2 的下游靶标和作用机制。
DR 模型中 NSUN2 和 RNA mC 甲基化的水平均显著升高。体外和体内敲低 NSUN2 均可减轻 DR 病变的形成。在机制上，NSUN2 通过与 RNA mC 阅读器 ALYREF 结合促进 MUC1 的表达。敲低 ALYREF 导致 DR 病变改变类似于 NSUN2 敲低观察到的改变。此外，MUC1 的过表达成功逆转了 NSUN2 沉默诱导的一系列 DR 改变。
NSUN2 通过 ALYREF 介导的 RNA mC 甲基化调节 MUC1 的表达，从而调节 DR 的进展，并为未来 DR 的治疗提供了新的选择。
