Fig. 4.
Instability of allele-specific expression during culture and in vitro differentiation of pluripotent cells. (A) Allele-specific reporter expression in differentiating cultures of early passage Dlk1MatTom/PatVen iPSCs derived in basal conditions (left column) or iPSCs derived in 3c at either early (P0, middle column) or higher (P5, third column) passage. Scale bar: 100 µm. (B) Gating strategy to define cells based on their Dlk1 expression pattern in 3c iPSCs maintained and differentiated in 4% or 20% oxygen; P5 cultures are shown. Red gates indicate maternal-only expression (mat), yellow gates show LOI expression and green gates indicate MOI. (C) Relative abundance of MOI (green), LOI (yellow) or maternal-only (red) cells in cultures expanded and differentiated at the indicated passage number in either 20% (top) or 4% (bottom) oxygen. (D) Same samples as in C but iPSCs expanded in 20% oxygen were differentiated in 4% oxygen (top panel) and iPSCs expanded in 4% oxygen were differentiated in 20% oxygen (bottom panel). Error bars indicate s.e. (n=3). (E) Possible applications of the Dlk1 reporter model to study genomic imprinting.