Fate changes leading to multipotency of isolated mesenchymal cells [ChIP-Seq]
Mesenchymal populations include a fraction of cells exhibiting multipotency as well as others with limited differentiation range. It has been assumed that the mesenchymal cellular cascade is topped by a multipotent cell, which gives rise to progeny with diminishing differentiation potentials.  Here we show that cultured mesenchymal cells, a priori exhibiting a limited differentiation potential, may gain new capacities and become multipotent following single cell isolation. These fate changes were accompanied by up-regulation of differentiation promoting genes, many of which also became H4K20me1 methylated. Early events in the process included TGFß and Wnt modulation, and down-regulation of hypoxia signaling. Indeed, hypoxic conditions inhibited the observed cell changes. Overall, cell isolation from neighboring partners caused major molecular changes and particularly, a newly established epigenetic state. It is suggested that MSCs behave non-deterministically and non-hierarchically and should therefore be defined primarily by their capacity to undergo fate changes triggered by environmental cues. Overall design: MSC 21 population and one of its derived clones (4L.1.4) were grown to confuence, and IP of fragmented DNA using an antibody directed against H4K20ME1, or non-immune serum (control) was done. Pulled DNA was then sequenced.