GSE36293
High-throughput sequencing of sequentially reprogrammed iPS cells reveals key epigenetic modifications correlated with reduced pluripotency of iPS cells [MeDIP-seq]
Full pluripotency of induced pluripotent stem (iPS) cells has been determined as viable all-iPS mice can be generated through tetraploid complementation. Subsequently, activation of imprinted Dlk-Dio3 gene cluster has been suggested to correlate with the pluripotency of iPS cells1. However, evidence from recent studies has demonstrated that loss of imprinting at the Dlk-Dio3 locus did not correlate strictly with the reduced pluripotency of iPS cells. Therefore, it becomes indispensable to exploit other reliable molecular markers for evaluating the quality of iPS cells accurately. In the present study, we successfully utilize the sequential reprogramming approach and produce all-iPS mice to six generations using iPS cell lines derived from different cell lineages which contain the same proviral integration in the genome. By comparing the global gene expression and epigenetic modifications of both “tetra-on” and corresponding “tetra-off” iPS cell lines established from either mesenchymal or hematopoietic lineages through deep sequencing analysis of mRNA expression, small RNA profiling, histone modifications (H3K4m2, H3K4me3 and H3K27me3) and DNA methylation, very few differences are detected among all the iPS cell lines investigated. However, we find that two imprinted genes, disruption of which correlate with the reduced pluripotency of iPS cells. Therefore, our data not only provide the first demonstration that producing of all-iPS mice to six generations is feasible, but reveal that two imprinted regions can be served as pluripotency markers of iPS cells Overall design: Examination of DNA methylation in 13 cell types