The contribution of lincRNAs at the interface between cell cycle regulation and cell state maintenance

We used single cell RNA-sequencing data of mouse embryonic stem cells (mESC) staged as G1, S, or G2/M to identify genes differentially expressed between these phases. We found differentially expressed lincRNAs to be enriched amongst cell cycle regulated genes. These cell cycle associated lincRNAs (CC-lincRNAs) are co-expressed with protein-coding genes with established roles in cell cycle progression. Interestingly, 70% of CC-lincRNAs are differentially expressed between G1 and S, suggesting they may contribute to the maintenance of the short G1 phase that characterizes the embryonic stem cell cycle. Consistent with this hypothesis, the promoters of CC-lincRNAs are enriched in pluripotency transcription factor binding sites, and their transcripts are frequently co-regulated with genes involved in the maintenance of pluripotency. We tested the impact of 2 CC-lincRNA candidates and show that modulation of their expression is associated with impaired cell cycle progression, further underlining the contribution of mESC-specific lincRNAs to cell cycle modulation in these cells.