RESUMEN
Embryonic stem cells differentiate efficiently in culture into neural progenitors, neurons, oligodendrocytes, and astrocytes. An embryonic stem (ES) cell line with green fluorescent protein (GFP) inserted into the gene for Olig2, a lineage-specific transcription factor, permits visualization and physical separation of a subset of living ES-cell-derived neural cells. GFP-expressing cells have morphological and antigenic properties of the oligodendrocyte lineage. The differentiation of living GFP-expressing cells can be followed in cultures, and they can be separated by fluorescence-activated cell sorting and cultured as pure populations. This system will allow detailed biochemical and molecular analysis of a neural differentiation pathway at a level not previously feasible. The strategy may have general applicability, since other neural lineages can be marked in an analogous manner.