ABSTRACT: Cited2 is a transcriptional regulator essential for embryonic development and cellular homeostasis. Studies in vertebrate models highlight its critical roles in heart, placental, neural tube, and hematopoietic development. In humans, CITED2 variants are associated to congenital heart disease. Functionally, Cited2 interacts with the transcriptional co-regulators p300/CBP and modulates the activity of multiple transcription factors. In embryonic stem cells (ESC), Cited2 supports pluripotency, self-renewal, and differentiation potential. Here, we performed comparative transcriptomic analysis after acute Cited2 depletion in mouse ESC to define its role in maintaining self-renewal, lineage competence, and cell survival. Loss of Cited2 rapidly destabilized the pluripotency network and induced aberrant activation of developmental gene programs. Nodal/Activin pathway targets, including key regulators of mesoderm, cardiac, and neural development, were markedly downregulated, consistent with Cited2-null embryonic phenotypes. Cited2 depletion also altered the expression of genes involved in DNA damage response, immune signaling, and apoptosis, correlating with the increased γH2AX accumulation and p53-dependent viability loss observed. Comparison with p300- and CBP-depletion datasets revealed minimal overlap, supporting a largely p300/CBP-independent role for Cited2 in ESC. These results position Cited2 as a core regulator preserving ESC identity, genomic stability, and proper lineage engagement during early differentiation.
