The novel role of hnRNP UL1 in human cell nucleoli

hnRNPUL1 plays an important role in the 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. Revealing its function, we figured out that hnRNP UL1 stimulates ribosomal DNA (rDNA) gene transcription. We have performed high-throughput sequencing of libraries prepared from nucleolar and cytoplasmic-nuclear RNA fractions to identify differentially expressed ribosomal RNAs in wild-type and HNRNPUL1 knockout HEK293T cells. We performed Nucleolar (NO) and Nuclear-Cytoplasmic (CN) fractionation of HEK293T wild-type and hnRNPUL1 knockout cells. The fractionated RNA was used to prepare libraries with biological triplicates from NO and CN RNA fractions from wild-type and HNRNPUL1KO cells.