Probably required for replication-independent chromatin assembly. Required for transcriptional silencing in the outer repeat (otr) centromeric repeats and the Tf2 long terminal repeat retrotransposons. Repressor of histone gene transcription in G1 arrested cells. Required for repression of htb1 gene expression outside of S phase. Interacts with his3 and slm9. Belongs to the WD repeat HIR1 family.