Dynamic Equilibrium and Heterogeneity of Mouse Pluripotent Stem Cells with Distinct Functional and Epigenetic States

Abstract

Embryonic stem cells (ESCs) are apparently homogeneous self-renewing cells, but we observed heterogeneous expression of Stella in ESCs, which is a marker of pluripotency and germ cells. Here we show that, whereas Stella-positive ESCs were like the inner cell mass (ICM), Stella-negative cells were like the epiblast cells. These states were interchangeable, which reflects the metastability and plasticity of ESCs. The established equilibrium was skewed reversibly in the absence of signals from feeder cells, which caused a marked shift toward an epiblast-like state, while trichostatin A, an inhibitor of histone deactelylase, restored Stella-positive population. The two populations also showed different histone modifications and striking functional differences, as judged by their potential for differentiation. The Stella-negative ESCs were more like the postimplantation epiblast-derived stem cells (EpiSCs), albeit the stella locus was repressed by DNA methylation in the latter, which signifies a robust epigenetic boundary between ESCs and EpiSCs.

Esrrb extinction triggers dismantling of naïve pluripotency and marks commitment to differentiation

“…In the post‐implantation epiblast, NANOG is re‐expressed (Hart et al , 2004; Osorno et al , 2012; Hoffman et al , 2013) but ESRRB is not (Adachi et al , 2013), likely due to differences in signaling environments between pre‐ and post‐implantation epiblasts. It is noteworthy that subpopulations of ESC cultures have been proposed to bear a similar character to primed pluripotent cells and vice versa (Hayashi et al , 2008; Han et al , 2010). Upon differentiation, naïve ESCs transit through a state (named EpiLCs) with transcriptional similarity to the early post‐implantation epiblast (Buecker et al , 2010; Hayashi et al , 2011).…”

Expression Dynamics and Functions of Hes Factors in Development and Diseases

“…In ES cells, Hes1 regulates Notch signaling molecules and cell cycle-related molecules, both of which are expressed in an oscillating manner in ES cells, suggesting that Hes1 oscillation sets the heterogeneous activation of Notch signaling and the variable timing of cell cycle exit in genetically identical ES cells (Kobayashi & Kageyama, 2010b). Other fluctuating molecules, including Nanog, Rex1, and Stella, have been identified in ES cells, so they may also contribute more diverse responses in cells to produce various kinds of cells at once even in the same environment (Chambers et al, 2007;Toyooka, et al, 2008;Hayashi, et al, 2008;Kobayashi & Kageyama, 2011). One attractive hypothesis is that such fluctuating and oscillatory expression of genes is a common feature of stem cells to endow them with their specific properties (Chang, et al, 2008;Furusawa & Kaneko, 2001.…”

A microRNA-Based System for Selecting and Maintaining the Pluripotent State in Human Induced Pluripotent Stem Cells

“…For instance, the pluripotency marker Stella shows a heterogeneous expression in mouse ESC cultures revealing the concomitant presence of two distinct but interchangeable cell populations with different developmental potential [38]. Moreover, by assessing clonal population through retroviral marking Stewart et al [39] tracked different subpopulations in human ESC/iPSC cultures with alternative capacity to be clonogenic, to participate in teratoma growth and to form EBs in vitro.…”