A shared Runx1-bound Zbtb16 enhancer directs innate and innate-like lymphoid lineage development.

Zbtb16-encoded PLZF is a signature transcription factor (TF) that directs the acquisition of T-helper effector programs during the development of multiple innate lymphocyte lineages, including natural killer T cell, innate lymphoid cell, mucosal-associated invariant T cell and γδ lineages. PLZF is also essential in osteoblast and spermatogonial development. How Zbtb16 itself is regulated in different lineages is incompletely understood. Here, by systematic CRISPR/Cas9-assisted deletions of chromatin accessible regions within the Zbtb16 locus in mouse, we identify a critical enhancer controlling PLZF expression exclusively in innate lymphoid lineages. Multiple sites within this enhancer express canonical motifs for the TF Runx1, which is essential for the development of these lineages. Notably, some regulatory sites control the kinetic rather than the overall level of PLZF expression. Thus, our comprehensive, unbiased analysis of regulatory elements in vivo reveals critical mechanisms of Zbtb16 regulation shared between innate and innate-like lymphoid lineages. Zbtb16-encoded transcription factor PLZF directs the differentiation of multiple innate and innate-like cell lineages, but how Zbtb16 itself is regulated remains unclear. Here the authors show, using CRISPR gene editing, ATAC-seq and ChIP-seq, that specific Runx1-bound enhancer elements critically modulate lineage-dependent expressions of PLZF.