Congrains Ada, Niemann Fernanda Soares, Duarte Adriana Da Silva Santos, Ferro Karla Priscila Vieira, Olalla-Saad Sara Teresinha
Hematology and Transfusion Medicine Center, University of Campinas, Campinas, Brazil.
Front Oncol. 2020 Nov 23;10:569668. doi: 10.3389/fonc.2020.569668. eCollection 2020.
is a key tumor suppressor in myeloid malignancy, mice lacking both and family member rapidly develop lethal acute myeloid leukemia (AML). We identified a long non-coding transcript in the locus and pursued the characterization of this anonymous transcript and the study of its role in leukemogenesis. We characterized this novel long non-coding transcript as a sense polyadenylated transcript. Bone marrow cells from AML patients expressed significantly reduced levels of lncNR4A3 compared to healthy controls (controls = 15, MDS= 20, p=0.05., AML= 21, p<0.01). Expression of , as previously reported, was also significantly reduced in AML. Interestingly, the expression of both coding and non-coding transcripts was highly correlated (Pearson R = 0.3771, P<0.01). Transient over-expression of LncNR4A3 by nucleofection led to an increase in the RNA and protein level of , reduction of proliferation in myeloid cell lines K-562 and KG1 (n=3 and 2 respectively, p<0.05) and reduced colony formation capacity in primary leukemic cells. A mass spectrometry-based quantitative proteomics approach was used to identify proteins dysregulated after lncNR4A3 over-expression in K-562. Enrichment analysis showed that the altered proteins are biologically connected (n=4, p<0.001) and functionally associated to RNA binding, transcription elongation, and splicing. Remarkably, we were able to validate the most significant results by WB. We showed that this novel transcript, lncNR4A3 regulates and we hypothesize this regulatory mechanism is mediated by the modulation of the RNA processing machinery.
是髓系恶性肿瘤中的关键肿瘤抑制因子，同时缺失 和家族成员 的小鼠会迅速发展为致命的急性髓系白血病（AML）。我们在 基因座中鉴定出一种长链非编码转录本，并对这种未知转录本进行了表征以及研究其在白血病发生中的作用。我们将这种新型长链非编码转录本表征为一种有义多聚腺苷酸化转录本。与健康对照相比，AML患者的骨髓细胞中lncNR4A3的表达水平显著降低（对照 = 15例，骨髓增生异常综合征 = 20例，p = 0.05；AML = 21例，p < 0.01）。如先前报道， 在AML中的表达也显著降低。有趣的是，编码和非编码转录本的表达高度相关（Pearson相关系数R = 0.3771，P < 0.01）。通过核转染瞬时过表达LncNR4A3导致 的RNA和蛋白质水平增加，髓系细胞系K - 562和KG1的增殖减少（分别为n = 3和2，p < 0.05），并且原代白血病细胞的集落形成能力降低。采用基于质谱的定量蛋白质组学方法来鉴定K - 562中lncNR4A3过表达后失调的蛋白质。富集分析表明，改变的蛋白质在生物学上相互关联（n = 4，p < 0.001），并且在功能上与RNA结合、转录延伸和剪接相关。值得注意的是，我们能够通过蛋白质免疫印迹法验证最显著的结果。我们表明这种新型转录本lncNR4A3调节 ，并且我们推测这种调节机制是由RNA加工机制的调节介导的。
