The localization of BAF complexes over the genome coincides with the major fate-determining factors of the cell type. For example, in ES cells, a BAF complex of specialized subunit composition not found in other cell types to date (esBAF) is found to co-bind strongly with each of the pluripotency factors (50). This observation is consistent with the findings of Rada-Iglesias and colleagues (52), who have shown that BAF complex binding is highly predictive of human enhancers. In addition, in murine ES cells, esBAF co-binds with Polycomb repressive complexes (Kadoch et al., unpublished data), which might reflect their opposition in much the same way the histone acetylases and deacetylase co-bind over the genome, reflecting their constant opposition and the highly labile nature of this histone modification (53).
