Functional Heterogeneity of Embryonic Stem Cells Revealed through Translational Amplification of an Early Endodermal Transcript
Figure 4
Microarray analyses of purified HV fractions.
Analyses of global gene expression in fractions defined by expression of the Venus transgene and SSEA-1. HV ES cells grown under self-renewing conditions were fractionated by flow cytometry into four fractions based on Venus (V) and SSEA-1 (S) expression. RNA was isolated from the following fractions: V−,S+; V+,S+; V−,S−; V+,S− and hybridised to a NIA Mouse 44K Microarray v2.1. (A) Heat map illustrating hierarchical clustering of differentially expressed genes identified in a pair-wise analysis of all four fractions. Significant changes in the expression of 2,169 genes (FDR <0.05) resulted in the identification of three to four expression groups, depending on whether clonal variation is taken into account. (B) Pair-wise comparisons (FDR <0.05, >1.5-fold expression levels) of the two ES cell populations, V+S+ and V−S+ depicted alongside the comparison between differentiated PrEn V+S− fraction and the Venus negative ES cell fraction (V−S+). (C) Gene expression changes characteristic of PrEn, ICM/pluripotency, neurectoderm, and mesoderm genes (expression of individual markers are included as supplementary, Figure S3). Plots are shown comparing mean log intensity values of genes among the four populations. Error bars (see supplementary data) represent standard deviation between expression levels in independent clonal lines of HV cells.