Regulator of Notch signaling, a signaling pathway involved in cell-cell communications that regulates a broad spectrum of cell-fate determinations. Probably acts both as a positive and negative regulator of Notch, depending on the developmental and cell context. Mediates the antineural activity of Notch, possibly by inhibiting the transcriptional activation mediated by MATCH1. Functions as an ubiquitin ligase protein in vitro, suggesting that it may regulate the Notch pathway via some ubiquitin ligase activity. Homodimer. May form a heterodimer with other members of the Deltex family. Interacts with NOTCH1. Belongs to the Deltex family. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.