Direct Reprogramming of Fibroblasts into Functional Mammary Epithelial cells by small molecules (RNAseq)

Mammary epithelial cells (MECs), the only cell type which could be capable of secreting milk in mammary gland, can be applied for the generation of transgenic mammary cell/gland bioreactor. However, continuously achieving large amount of high-quality goat MECs by non-invasion method, especially prepuberal MECs, in vitro has been a challenge. Here, we show that a small molecules cocktail enables the in vitro generation of chemically-induced mammary epithelial cells (CiMECs) with milk-secreting properties from goat ear fibroblasts. The properties of CiMECs were highly similar to those of naturally isolated MECs. Notably, the CiMECs lineage reprogramming process may partially imitate the MECs developmental process from embryonic to milk-secreting stages. Interestingly, fibroblasts were firstly reversed back to embryonic ectoderm/surface ectoderm-like state. Our findings constitute a substantial step toward further promoting the application of transgenic mammary bioreactors, moreover, also offer a new strategy for obtaining other cell types by reprogrammed fibroblasts. Overall design: The twenty three samples are analyzed. BERTV0d and GMECs are control group with three replicates. BFRTV1d/2d/3d/6d are treatment group with three replicates.BFRTV4d, BFRTV8d and CiMECs are treatment group with three replicates.