Predicted to enable methylated histone binding activity and transcription cis-regulatory region binding activity. Predicted to contribute to histone methyltransferase activity (H3-K4 specific). Acts upstream of or within histone H3-K4 methylation. Predicted to be located in nucleolus and nucleoplasm. Predicted to be part of MLL1 complex; MLL3/4 complex; and Set1C/COMPASS complex. Is expressed in cerebral cortex and genitourinary system. Orthologous to human RBBP5 (RB binding protein 5, histone lysine methyltransferase complex subunit). [provided by Alliance of Genome Resources, Apr 2022]