S5 F). T cell subsets, ILCs previously could be classified into three subgroups, namely group 1 ILC (ILC1s), group 2 ILC (ILC2s), and group 3 ILC (ILC3s), relating Gamitrinib TPP hexafluorophosphate to presented cytokine profiles and fate-decision transcription factors (TFs; Eberl et al., 2015; Serafini et al., 2015). We recently defined a new regulatory subpopulation of ILCs named ILCregs (Wang et al., 2017b). ILC1s are characterized by expressing T-bet and generating type 1 cytokine IFN-, which is essential for clearance of intracellular microbial infections (Bernink et al., 2015). ILC2s require Gata3 for his or her differentiation and maintenance (Hoyler et al., 2012; Mj?sberg et al., 2012). After activation by IL-25 and IL-33, Gamitrinib TPP hexafluorophosphate ILC2s generate type 2 cytokines, such as IL-5 and IL-13, to promote resolution of helminth infections (Brestoff et al., 2015) and participate in pathogenesis of asthma (Sui et al., 2018). ILC3s are a heterogeneous lineage including lymphoid cells inducer (LTi) cells, NKp46+ ILC3s, and CCR6?NKp46? ILC3s (Serafini et al., 2015). ILC3s are defined by RORt manifestation and are a main source of NPM1 type 17 cytokines, such as IL-22 and IL-17, which are extremely critical for resistance against bacterial infections (Diefenbach et al., 2017). ILCregs are a group of IL-10Cgenerating cells that suppress activation of ILC1s and ILC3s to regulate the inflammatory response. All ILCs, as well as natural killer (NK), B, and T cells, are derived from common lymphoid progenitors (CLPs) in bone marrow (BM; Diefenbach et al., 2014). CLPs can differentiate into -lymphoid progenitors (LPs; CXCR+ integrin 47Cexpressing CLPs; Yu et al., 2014), which lack the potential to generate B and T cells. A recent study showed that LPs are quite heterogeneous and consist of early innate lymphoid progenitors, common helper ILC progenitors (CHILPs), and ILC precursors (ILCPs; Seillet et al., 2016). CHILPs can differentiate into downstream ILCPs that give rise to all ILCs but without LTi cells and ILCregs (Constantinides et al., 2014; Wang et al., 2017b). Besides cytokine signaling, ILC lineage differentiation is definitely delicately controlled by fate-decision TFs (Vivier et al., 2018). For instance, Tox, Nfil3, and Tcf1 are required for CLP differentiation toward LPs (Yu et al., 2014; Seehus et al., 2015; Yang et al., 2015). Id2 participates in the generation of CHILPs, and PLZF directs ILCP production (Constantinides et al., 2014; Klose et al., 2014). Gamitrinib TPP hexafluorophosphate Id3 drives the differentiation of CHILPs toward ILCregs (Wang et al., 2017b). However, how CLPs stratify and differentiate into ILC lineages still requires further investigation. Chromatin structures are extremely dynamic for genetic reading and transcription and may be revised by several means, including ATP-dependent chromatin redesigning, incorporation of histone variants, DNA methylation, and histone modifications (Zhou et al., 2016). The best-defined histone modifications are composed of acetylation, phosphorylation, methylation, ubiquitination, and sumoylation (Zentner and Henikoff, 2013). Yeats domainCcontaining proteins are conserved from candida to human and include Yeats4 (also named as GAS41), ENL, Yeats2, and AF9 in human being (Hsu et al., 2018; Wang et al., 2018). These Yeats domainCcontaining proteins are involved in histone acetylation acknowledgement and gene transcription by redesigning chromatin constructions (Schulze et al., 2009; Li et al., 2014). It has been reported that Yeats4 can identify histone acetylation and facilitate lung malignancy progression (Hsu et al., 2018; Klein et al., 2018). ENL also recognizes histone acetylation to promote oncogenic gene manifestation (Erb et al., 2017; Wan et Gamitrinib TPP hexafluorophosphate al., 2017). Yeats2 functions as an H3K27ac reader to regulate gene transcription (Mi et al., 2017). However, how YEATS domainCcontaining proteins regulate ILC development and differentiation is definitely unclear. Here, we display that Yeats4 is required for 47+ CLP differentiation toward ILCs. Yeats4 recognizes H3K27ac Gamitrinib TPP hexafluorophosphate to recruit the Dot1CRNA polymerase (Pol) II.