Laboratory of RNA Processing, Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Uniwersytetu Poznańskiego 6, 61-614 Poznan, Poland.
Center for Advanced Technology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 10, 61-614 Poznan, Poland.
Int J Biol Sci. 2022 Jul 18;18(13):4809-4823. doi: 10.7150/ijbs.75084. eCollection 2022.
hnRNP UL1 plays an important role in cell nuclei, where it is recruited to DNA damage sites and is involved in the repair of DNA double-strand breaks. Furthermore, this protein is known as a transcriptional repressor of RNA polymerase II genes. In the present study, we have shown that hnRNP UL1 is also localized in the nucleoli of human cells. Upon investigating its function, we found that hnRNP UL1 stimulates ribosomal DNA (rDNA) gene transcription. Moreover, we observed that cells with hnRNP UL1 silencing exhibited increased sensitivity to DNA damage. We also showed that hnRNP UL1 interacts with γH2A.X, RPA32, XRCC1, and Chk1 in cell nucleoli, suggesting its involvement in the repair of rDNA damage.
hnRNP UL1 在细胞核中发挥着重要作用，它被招募到 DNA 损伤部位，并参与 DNA 双链断裂的修复。此外，这种蛋白质被认为是 RNA 聚合酶 II 基因的转录抑制剂。在本研究中，我们已经表明 hnRNP UL1 也定位于人类细胞的核仁中。在研究其功能时，我们发现 hnRNP UL1 可刺激核糖体 DNA（rDNA）基因转录。此外，我们观察到沉默 hnRNP UL1 的细胞对 DNA 损伤的敏感性增加。我们还表明，hnRNP UL1 与核仁中的 γH2A.X、RPA32、XRCC1 和 Chk1 相互作用，提示其参与 rDNA 损伤的修复。
