Expanding the Chinese hamster ovary cell long non-coding RNA transcriptome using RNASeq

Our ability to study Chinese hamster ovary (CHO) cell biology has been revolutionised over the last decade with the development of next generation sequencing and the publication of reference DNA sequences for CHO cells and the Chinese hamster. RNA sequencing has not only enabled the association of transcript expression with bioreactor conditions and desirable bioprocess phenotypes but played a key role in the characterisation of protein coding and small non-coding RNAs. The annotation of long non-coding RNAs, and therefore our understanding of their role in CHO cell biology, has been limited to date. In this manuscript, we use high resolution RNASeq data to more than double the number of annotated lncRNA transcripts for the CHOK1 genome. In addition, the utilisation of strand specific sequencing enabled the identification of more than 1,000 new lncRNAs located antisense to protein coding genes. The utility of monitoring lncRNA expression is demonstrated through an analysis of the transcriptomic response to a reduction of cell culture temperature and identification of simultaneous sense/antisense differential expression for the first time in CHO cells. To enable further studies of lncRNAs, the transcripts annotated in this study have been made available for the CHO cell biology community.