KRT18与mRNA及长链非编码RNA互作调控椎间盘髓核细胞损伤的机制  

Mechanism by which KRT18 interacts with mRNA and long non-coding RNA to regulate intervertebral disc nucleus pulposus cell injury

作　　者：刘钟元 李扬 张志文 Liu Zhongyuan;Li Yang;Zhang Zhiwen(College of Acupuncture and Orthopedics,Hubei University of Chinese Medicine,Wuhan 430061,Hubei Province,China;Hospital affiliated to Hubei University of Traditional Chinese Medicine,Hubei Hospital of Traditional Chinese Medicine,Hubei Institute of Traditional Chinese Medicine,Wuhan 430061,Hubei Province,China)

机构地区：[1]湖北中医药大学针灸骨伤学院,湖北省武汉市430061 [2]湖北中医药大学附属医院、湖北省中医院、湖北省中医药研究院,湖北省武汉市430061

出　　处：《中国组织工程研究》2025年第2期312-321,共10页Chinese Journal of Tissue Engineering Research

基　　金：湖北省自然科学基金项目(2022CFB406),项目负责人:张志文。

摘　　要：背景:椎间盘中差异表达的RNA结合蛋白在椎间盘退变中发挥着关键作用,其中RNA结合蛋白KRT18水平的降低与椎间盘退行性病变相关,但其在椎间盘髓核细胞中的具体作用尚未完全确定。目的:探讨KRT18与mRNA及长链非编码RNA结合互作对椎间盘髓核细胞的影响及机制。方法:对因腰部骨折或椎间盘退行性病变而接受椎间融合术的患者进行人体髓核组织取样获得正常髓核细胞和退变髓核细胞,并进行iRIP-seq、功能富集分析以及DNA微阵列分析,随后根据分析结果在髓核细胞中敲低KRT18,通过蛋白免疫印迹及qRt-PCR在蛋白和RNA水平检测相关基因水平的表达。结果与结论:通过iRIP-seq分析发现GUAAUC和AGCCUC序列中存在大量的KRT18结合位点,表明KRT18可参与调控RNA的转录、翻译、稳定性或在细胞信号传导途径中发挥作用。其能够与成熟的mRNA稳定结合,其中表达较高的基因包括CRLF1及IGFBP4等,同时与其结合的长链非编码RNA的峰值基因包括SNHG25、SNHG12、NEAT1、USP32、EIF4A2和CDH4,这些基因多涉及细胞凋亡、炎症等多种生物过程,并且能介导细胞外基质代谢的相关通路,KRT18能够调控它们的稳定性、转运、翻译、剪接等多个方面的功能,进而影响基因的表达和细胞功能。实验结果验证了在髓核细胞中敲低KRT18,细胞外基质代谢水平被抑制出现失衡,导致体外椎间盘退变。该研究首次从KRT18与mRNA及长链非编码RNA结合的角度探讨其调控机制,并推测了KRT18在椎间盘退变发病机制中的潜在功能,为今后KRT18关键功能的研究奠定了基础。BACKGROUND:Differentially expressed RNA-binding proteins in the intervertebral disc plays a key role in intervertebral disc degeneration,and decreased levels of the RNA-binding protein KRT18 are associated with degenerative disc disease,but its specific role in the nucleus pulposus cells has not yet been fully determined.OBJECTIVE:To investigate the interaction of KRT18 with mRNA and long non-coding RNA on nucleus pulposus cells of the intervertebral disc and its mechanism.METHODS:Normal and degenerated nucleus pulposus cells were obtained from nucleus pulposus samples of patients undergoing interbody fusion for lumbar fracture or intervertebral disc degeneration.iRIP-seq,functional enrichment analysis,and DNA microarray analysis were performed to identify the mRNA and long non-coding RNA binding with KRT18.Subsequently,KRT18 was knocked down in nucleus pulposus cells based on the analysis results,and the expression levels of related genes were detected at the protein and RNA levels through protein immunoblotting and qRT-PCR,respectively.RESULTS AND CONCLUSION:Through iRIP-seq analysis,we identified abundant KRT18 binding sites within the GUAAUC and AGCCUC sequences,indicating that KRT18 may be involved in regulating RNA transcription,translation,stability or play a role in cell signaling pathways.It can stably bind to mature mRNA,among which highly expressed genes include CRLF1,IGFBP4,etc.At the same time,the peak genes of long non-coding RNA binding with it include SNHG25,SNHG12,NEAT1,USP32,EIF4A2 and CDH4.Most of these genes are involved in various biological processes such as apoptosis and inflammation,and can mediate related pathways of extracellular matrix metabolism.KRT18 can regulate their stability,transport,translation,splicing and other functions,thus affecting gene expression and cell function.We further verified through experiments the knockdown of KRT18 in nucleus pulposus cells,and found that the level of extracellular matrix metabolism was inhibited and unbalanced,resulting in intervertebral disc

关 键 词：椎间盘退行性变 RNA结合蛋白 KRT18 iRIP-seq MRNA 长链非编码RNA 

分 类 号：R496[医药卫生—康复医学] R318[医药卫生—临床医学] R681