RBPJ (Recombination Signal Binding Protein For Immunoglobulin Kappa J Region): RBPJ is a key transcription factor in the Notch signaling pathway, which plays a critical role in regulating cell fate, differentiation, and development. Proper function of RBPJ is essential for tissue development and cell specialization, while dysregulation of RBPJ and Notch signaling is associated with various diseases, including cancers and developmental disorders.