The chromatin remodeler Chd4 maintains embryonic stem cell identity by controlling pluripotency- and differentiation-associated genesThe unique properties of embryonic stem cells (ESCs), including unlimited self-renewal and pluripotent differentiation potential, are sustained by integrated genetic and epigenetic networks composed of transcriptional factors and epigenetic modulators. However, the molecular mechanisms underlying the function of these regulators are not fully elucidated. Chromodomain helicase DNA-binding protein 4 (Chd4), an ATPase subunit of the nucleosome remodeling and deacetylase (NuRD) complex, is highly expressed in ESCs.
miR-21-mediated Radioresistance Occurs via Promoting Repair of DNA Double Strand BreaksmiR-21, as an oncogene that overexpresses in most human tumors, is involved in radioresistance; however, the mechanism remains unclear. Here, we demonstrate that miR-21-mediated radioresistance occurs through promoting repair of DNA double strand breaks, which includes facilitating both non-homologous end-joining (NHEJ) and homologous recombination repair (HRR). The miR-21-promoted NHEJ occurs through targeting GSK3B (a novel target of miR-21), which affects the CRY2/PP5 pathway and in turn increases DNA-PKcs activity.