Deciphering the mesodermal potency of porcine skin-derived progenitors (SKP) by microarray analysis.

Skin stem cells have an essential role in maintaining tissue homeostasis by dynamically replenishing those constantly lost during tissue turnover or following injury. Multipotent skin derived progenitors (SKP) can generate both neural and mesodermal progeny, representing neural crest-derived progenitors during embryogenesis through adulthood. SKP cells develop into spheres in suspension and can differentiate into fibroblast-like cells (SFC) in adhesive culture with serum. Concomitantly they gradually lose the neural potential but retain certain mesodermal potential. However, little is known about the molecular mechanism of the transition of SKP spheres into SFC in vitro. Here we characterized the transcriptional profiles of porcine SKP spheres and SFC by microarray analysis. We found 305 upregulated and 96 downregulated genes, respectively. The downregulated genes are mostly involved in intrinsic programs like the Dicer pathway and asymmetric cell division, whereas upregulated genes are likely to participate in extrinsic signaling pathways such as ErbB signaling, MAPK signaling, ECM-receptor reaction, Wnt signaling, cell communication, and tumor growth factor (TGF)-β signaling pathways. These intrinsic programs and extrinsic signaling pathways collaborate to mediate the transcription-state transition between SKP spheres and SFC. We speculate that these potential signaling pathways may play an important role in regulating the cell fate transition between SKP spheres and SFC in vitro.