Ubiquitin-like, containing PHD and RING finger domains, 1, also known as UHRF1, is a protein which in humans is encoded by the UHRF1 gene.

This gene encodes a member of a subfamily of RING-finger type E3 ubiquitin ligases. The protein binds to specific DNA sequences, and recruits a histone deacetylase to regulate gene expression. Its expression peaks at late G1 phase and continues during G2 and M phases of the cell cycle. It plays a major role in the G1/S transition by regulating topoisomerase IIalpha and retinoblastoma gene expression, and functions in the p53-dependent DNA damage checkpoint. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq].
Function: Putative E3 ubiquitin-protein ligase. May participate in methylation-dependent transcriptional regulation. Binds to inverted 5'-CCAAT-3' box 2 in the TOP2A promoter, and activates TOP2A expression. Important for G1/S transition. May be involved in DNA repair and chromosomal stability.