Partially Reprogrammed Induced Pluripotent Stem Cells Using MicroRNA Cluster miR-302s in Guangxi Bama Minipig Fibroblasts

Pig-induced pluripotent stem cells (piPSCs) have great potential application in regenerative medicine. The miR-302s cluster alone has been shown to reprogram mouse and human somatic cells into induced pluripotent stem cells (iPSCs) without exogenous transcription factors. However, miR-302s alone have not been reported to reprogram cells in large livestock. In this study, we induced pig somatic cells into partially reprogrammed piPSCs using overexpression of the miR-302s cluster (miR-302s-piPSC) and investigated the early reprogramming events during the miRNA induction process. The results showed that miR-302s-piPSCs exhibited some characteristics of pluripotent stem cells including expression of pluripotency markers-particularly, efficient activation of endogenous OCT4-and differentiation to the three germ layers in vitro. During the early reprogramming process, somatic cells first underwent epithelial-mesenchymal transition and then mesenchymal-epithelial transition to eventually form miR-302s-piPSCs. These data show, for the first time, that single factor miR-302s successfully induced pig somatic cells into miR-302s-piPSCs. This study provides a new tool and research direction for the induction of pluripotent stem cells in a large livestock.