The chromatin reader DIDO3 is a regulator of the gene network that controls B cell differentiation.

The development of hematopoietic cell lineages is a highly complex process that is governed by a delicate interplay of various transcription factors. The expression of these factors is influenced, in part, by epigenetic signatures that define each stage of cell differentiation. In particular, the formation of B lymphocytes depends on the sequential silencing of stemness genes and the balanced expression of interdependent transcription factors, along with DNA rearrangement. We have investigated the impact that the deficiency of DIDO3, a protein involved in chromatin status readout, has on B cell differentiation within the hematopoietic compartment of mice. Our findings revealed significant impairments in the successive stages of B cell development. The absence of DIDO3 resulted in remarkable alterations in the expression of essential transcription factors and differentiation markers, which are crucial for orchestrating the differentiation process. In addition, the somatic recombination process, which is responsible for generation of antigen receptor diversity, was also adversely affected. These observations highlight the vital role of epigenetic regulation, in particular the involvement of DIDO3, in ensuring proper B cell differentiation. Further research into the mechanisms underlying these disruptive alterations will deepen our understanding of hematopoiesis and may potentially lead to insights that aid in the development of therapeutic interventions for disorders involving aberrant B cell development. Overall design: ChIP-Seq analysis of DIDO3 wild-type and E16 mutant in hematopoietic precursors (LSK, lin-Kit+Sca1+) cells.