To get mechanistic insight into the molecular mechanisms of lncRNA SNHG26, we transduced HaCaT cells stably expressing catalytically inactive CAS9, dead CAS9 (dCAS9), fused with either the Krüppel-associated box (KRAB) repressing domain (CRISPRi) or multiple activating domains (CRISPRa) with SNHG26-specific gRNA or a non-target control gRNA followed by RNA sequencing. Transcriptional inhibition (CRISPRi) or activation (CRISPRa) of lncRNA SNHG26 in HaCaT cells

Long noncoding RNAs (lncRNAs) are involved in the regulation of cell cycle, although only a few have been functionally characterized. By combining RNA sequencing and ChIP sequencing of cell cycle synchronized HaCaT cells we have previously identified lncRNAs highly enriched for cell cycle functions. Based on a cyclic expression profile and an overall high correlation to histone 3 lysine 4 trimethylation (H3K4me3) and RNA polymerase II (Pol II) signals, the lncRNA SNHG26 was identified as a top candidate. In the present study we report that downregulation of SNHG26 affects mitochondrial stress, proliferation, cell cycle phase distribution, and gene expression in cis- and in trans, and that this effect is reversed by upregulation of SNHG26. We also find that the effect on cell cycle phase distribution is cell type specific and stable over time. Results indicate an oncogenic role of SNHG26, possibly by affecting cell cycle progression through the regulation of downstream MYC-responsive genes.