ADNP regulates chromatin architecture and lineage fidelity during neural differentiation.

Transition from a pluripotent to a differentiated cell state is accompanied by significant changes in genome organization. Activity dependent neuroprotective protein (ADNP) is a chromatin regulator with critical roles in neurodevelopment and limits the genomic occupancy of CTCF, a master architectural protein in genome organization, in embryonic stem cells. However, ADNP localization, function, and relationship with CTCF in differentiated neural lineages are not well studied. Here we develop a dual degron model which allows us to acutely deplete ADNP in neural progenitor cells (NPCs). We find that ADNP depletion does not impact NPC survival in the short term, but results in a genome organization switch, which favors the formation of short-range chromatin looping interactions coinciding with CTCF accumulation. Furthermore, ADNP localizes to active gene promoters in NPCs that are unoccupied by CTCF, where it prevents over-expression of genes that are activated upon neurodifferentiation and represses those involved in commitment to other lineages. Our findings uncover CTCF-dependent as well as CTCF-independent regulatory mechanisms of ADNP in NPC-specific chromatin organization and gene expression programs that may underlie its essential function in neurodevelopment.