The zinc finger protein 521 (ZNF521) is a transcription factor containing an N-terminal transcriptional repressor motif and 30 zinc finger domains. It plays a role in both erythroid cell and osteoblast differentiation during development, inhibiting the activities of early B-cell factor 1 (EBF1) in erythroid cells and Runx2 in osteoblast precursors. ZFP521 binds to both Runx2 and histone deacetylase 3 (HDAC3), promotes their association and antagonizes Runx2 transcriptional activity in a HDAC3-dependent manner, thereby regulating osteoblast differentiation, skeletal development, and bone homeostasis.
