Disruption of cell:cell contact promotes the establishment of the mesoderm lineage while MEDII has an opposing activity that promotes formation of neurectoderm.

<p>EPL cells were dissociated and reaggregated in unsupplemented tissue culture medium (○) or medium supplemented with 50% MEDII (▴). Alternatively, EPL cells were maintained in aggregates and transferred to unsupplemented tissue culture medium (□) or medium supplemented with 50% MEDII (♦). Aggregates were collected daily to day 7 and analyzed by real-time PCR for the expression of markers of primitive streak, EMT and differentiated lineages. Gene expression was normalized to <i>β-actin</i> (here) and <i>GAPDH</i> (data not shown); the relative gene expression seen with either housekeeping gene was comparable. n = 4 independent experiments, error bars represent sem. MEDII⁺/Dis⁻EBs were only included where changes in gene expression were detected.