长链非编码RNA HMS招募RNA结合蛋白HuR以稳定HOXC10信使核糖核酸的3'非翻译区。
The lncRNA HMS recruits RNA-binding protein HuR to stabilize the 3'-UTR of HOXC10 mRNA.
作者信息
Priyanka Priyanka, Sharma Madhur, Das Sanjeev, Saxena Sandeep
机构信息
DNA Replication and Cell Cycle Laboratory, National Institute of Immunology, New Delhi, India.
Departmeny of Biochemistry, UDSC, New Delhi, India.
出版信息
J Biol Chem. 2021 Aug;297(2):100997. doi: 10.1016/j.jbc.2021.100997. Epub 2021 Jul 22.
Long noncoding RNAs (lncRNAs) have been reported to drive key cancer pathways but the functions of majority of lncRNAs are unknown making a case for comprehensive functional evaluation of lncRNAs. With an aim to identify lncRNAs dysregulated in human cancers, we analyzed the cancer patient database of lung adenocarcinoma (LUAD), which revealed an upregulated lncRNA, LINC02381 (renamed HOXC10mRNA stabilizing factor or HMS in this study), whose depletion results in proliferation defects and inhibition of colony formation of human cancer cells. In order to identify the binding targets of HMS, we screened for cis-genes and discovered that HOXC10, an oncogene, is downregulated in the absence of HMS. Depletion of HMS does not affect the HOXC10 promoter activity but inhibits the HOXC10 3'-UTR-linked luciferase reporter activity. Since lncRNAs have been known to associate with RNA-binding proteins (RBPs) to stabilize mRNA transcripts, we screened for different RBPs and discovered that HuR, an ELAV family protein, stabilizes HOXC10 mRNA. Using RNA pull-down and deletion mapping experiments, we show that HuR physically interacts with the cytosine-rich stretch of HMS and HOXC10 3'-UTR to stabilize HOXC10 mRNA. HOXC10 is overexpressed in many human cancers, and our discovery highlights that lncRNA HMS sustains the HOXC10 mRNA levels to maintain the invasive phenotypes of cancer cells.
据报道,长链非编码RNA(lncRNA)可驱动关键的癌症通路,但大多数lncRNA的功能尚不清楚,因此有必要对lncRNA进行全面的功能评估。为了鉴定在人类癌症中失调的lncRNA,我们分析了肺腺癌(LUAD)的癌症患者数据库,结果显示一种lncRNA,即LINC02381(本研究中重新命名为HOXC10 mRNA稳定因子或HMS)上调,其缺失会导致人类癌细胞的增殖缺陷和集落形成受到抑制。为了鉴定HMS的结合靶点,我们筛选了顺式作用基因,发现癌基因HOXC10在缺乏HMS时表达下调。HMS的缺失不影响HOXC10启动子活性,但抑制HOXC10 3'-UTR连接的荧光素酶报告基因活性。由于已知lncRNA可与RNA结合蛋白(RBP)结合以稳定mRNA转录本,我们筛选了不同的RBP,发现ELAV家族蛋白HuR可稳定HOXC10 mRNA。通过RNA下拉和缺失定位实验,我们表明HuR与HMS富含胞嘧啶的区域以及HOXC10 3'-UTR发生物理相互作用,从而稳定HOXC10 mRNA。HOXC10在许多人类癌症中过表达,我们的发现突出表明lncRNA HMS维持HOXC10 mRNA水平以维持癌细胞的侵袭表型。